I have briefly abstracted these opinions for the sake of showing those who have never attended to such subjects, how perplexing they are. It would, therefore, be useless for my purpose to give a sketch of the conspicuous differences between the several forms. Besides the ever-recurrent difficulty of determining whether forms found wild are truly aboriginal or are escaped seedlings, many of the forms, which must be ranked as varieties, transmit their characters almost perfectly by seed. Sweet and bitter oranges differ in no important respect except in the flavour of their fruit, but Gallesio (10/14. 'Teoria della Riproduzione' pages 52-57.) is most emphatic that both kinds can be propagated by seed with absolute certainty. Consequently, in accordance with his simple rule, he classes them as distinct species; as he does sweet and bitter almonds, the peach and nectarine, etc. He admits, however, that the soft-shelled pine-tree produces not only soft-shelled but some hard-shelled seedlings, so that a little greater force in the power of inheritance would, according to this rule, raise a soft-shelled pine-tree into the dignity of an aboriginally created species. The positive assertion made by Macfayden (10/15. Hooker 'Bot. Misc.' volume 1 page 302; volume 2 page 111.) that the pips of sweet oranges produced in Jamaica, according to the nature of the soil in which they are sown, either sweet or bitter oranges, is probably an error; for M. Alph. De Candolle informs me that since the publication of his great work he has received accounts from Guiana, the Antilles, and Mauritius, that in these countries sweet oranges faithfully transmit their character. Gallesio found that the willow-leafed and the Little China oranges reproduced their proper leaves and fruit; but the seedlings were not quite equal in merit to their parents. The red-fleshed orange, on the other hand, fails to reproduce itself. Gallesio also observed that the seeds of several other singular varieties all reproduced trees having a peculiar physiognomy, partly resembling their parent-forms. I can adduce another case: the myrtle leaved orange is ranked by all authors as a variety, but is very distinct in general aspect: in my father's greenhouse, during many years, it rarely yielded any fruit, but at last produced one; and a tree thus raised was identical with the parent-form.

Another and more serious difficulty in determining the rank of the several forms is that, according to Gallesio (10/16. 'Teoria della Riproduzione' page 53.) they largely intercross without artificial aid; thus he positively states that seeds taken from lemon-trees (C. lemonum) growing mingled with the citron (C. medica), which is generally considered as a distinct species, produced a graduated series of varieties between these two forms. Again, an Adam's apple was produced from the seed of a sweet orange, which grew close to lemons and citrons. But such facts hardly aid us in determining whether to rank these forms as species or varieties; for it is now known that undoubted species of Verbascum, Cistus, Primula, Salix, etc., frequently cross in a state of nature. If indeed it were proved that plants of the orange tribe raised from these crosses were even partially sterile, it would be a strong argument in favour of their rank as species. Gallesio asserts that this is the case; but he does not distinguish between sterility from hybridism and from the effects of culture; and he almost destroys the force of this statement by another (10/17. Gallesio 'Teoria della Riproduzione' page 69.) namely, that when he impregnated the flowers of the common orange with the pollen taken from undoubted VARIETIES of the orange, monstrous fruits were produced, which included "little pulp, and had no seeds, or imperfect seeds."

In this tribe of plants we meet with instances of two highly remarkable facts in vegetable physiology: Gallesio (10/18. Ibid page 67.) impregnated an orange with pollen from a lemon, and the fruit borne on the mother tree had a raised stripe of peel like that of a lemon both in colour and taste, but the pulp was like that of an orange and included only imperfect seeds. The possibility of pollen from one variety or species directly affecting the fruit produced by another variety of species, is a subject which I shall fully discuss in the following chapter.

The second remarkable fact is, that two supposed hybrids (10/19. Gallesio 'Teoria della Riproduzione' pages 75, 76.) (for their hybrid nature was not ascertained), between an orange and either a lemon or citron, produced on the same tree leaves, flowers, and fruit of both pure parent-forms, as well as of a mixed or crossed nature. A bud taken from any one of the branches and grafted on another tree produces either one of the pure kinds or a capricious tree reproducing the three kinds. Whether the sweet lemon, which includes within the same fruit segments of differently flavoured pulp (10/20. 'Gardener's Chronicle' 1841 page 613.), is an analogous case, I know not. But to this subject I shall have to recur.

I will conclude by giving from A. Risso (10/21. 'Annales du Museum' tome 20 page 188.) a short account of a very singular variety of the common orange. It is the "citrus aurantium fructu variabili," which on the young shoots produces rounded-oval leaves spotted with yellow, borne on petioles with heart-shaped wings; when these leaves fall off, they are succeeded by longer and narrower leaves, with undulated margins, of a pale-green colour embroidered with yellow, borne on footstalks without wings. The fruit whilst young is pear-shaped, yellow, longitudinally striated, and sweet; but as it ripens, it becomes spherical, of a reddish-yellow, and bitter.

PEACH AND NECTARINE (Amygdalus persica).

The best authorities are nearly unanimous that the peach has never been found wild. It was introduced from Persia into Europe a little before the Christian era, and at this period few varieties existed. Alph. De Candolle (10/22. 'Geograph. Bot.' page 882.), from the fact of the peach not having spread from Persia at an earlier period, and from its not having pure Sanscrit or Hebrew names, believes that it is not an aboriginal of Western Asia, but came from the terra incognita of China. The supposition, however, that the peach is a modified almond which acquired its present character at a comparatively late period, would, I presume, account for these facts; on the same principle that the nectarine, the offspring of the peach, has few native names, and became known in Europe at a still later period.

(FIGURE 42.-PEACH AND ALMOND STONES, of natural size, viewed edgeways. 1. Common English peach. 2. Double, crimson-flowered, Chinese Peach. 3. Chinese Honey Peach. 4. English Almond. 5. Barcelona Almond. 6. Malaga Almond. 7. Soft-shelled French Almond. 8. Smyrna Almond.)

Andrew Knight (10/23. 'Transactions of Hort. Soc.' volume 3 page 1 and volume 4 page 396 and note to page 370. A coloured drawing is given of this hybrid.), from finding that a seedling-tree, raised from a sweet almond fertilised by the pollen of a peach, yielded fruit quite like that of a peach, suspected that the peach-tree is a modified almond; and in this he has been followed by various authors. (10/24. 'Gardener's Chronicle' 1856 page 532. A writer, it may be presumed Dr. Lindley, remarks on the perfect series which may be formed between the almond and the peach. Another high authority, Mr. Rivers, who has had such wide experience, strongly suspects ('Gardener's Chronicle' 1863 page 27) that peaches, if left to a state of nature, would in the course of time retrograde into thick-fleshed almonds.) A first-rate peach, almost globular in shape, formed of soft and sweet pulp, surrounding a hard, much furrowed, and slightly flattened stone, certainly differs greatly from an almond, with its soft, slightly furrowed, much flattened, and elongated stone, protected by a tough, greenish layer of bitter flesh. Mr. Bentham (10/25. 'Journal of Hort. Soc.' volume 9 page 168.) has particularly called attention to the stone of the almond being so much more flattened than that of the peach. But in the several varieties of the almond, the stone differs greatly in the degree to which it is compressed, in size, shape, strength, and in the depth of the furrows, as may be seen in figure 42 (Nos. 4 to 8) of such kinds as I have been able to collect. With peach-stones also (Nos. 1 to 3) the degree of compression and elongation is seen to vary; so that the stone of the Chinese Honey-peach (No. 3) is much more elongated and compressed than that of the (No. 8) Smyrna almond. Mr. Rivers, of Sawbridgeworth, to whom I am indebted for some of the specimens above figured, and who has had such great horticultural experience, has called my attention to several varieties which connect the almond and the peach. In France there is a variety called the Peach-Almond, which Mr. Rivers formerly cultivated, and which is correctly described in a French catalogue as being oval and swollen, with the aspect of a peach, including a hard stone surrounded by a fleshy covering, which is sometimes eatable. (10/26. Whether this is the same variety as one lately mentioned ('Gardener's Chronicle' 1865 page 1154) by M. Carriere under the name of persica intermedia, I know not; this variety is said to be intermediate in nearly all its characters between the almond and peach; it produces during successive years very different kinds of fruit.) A remarkable statement by M. Luizet has recently appeared in the 'Revue Horticole' (10/27. Quoted in 'Gardener's Chronicle' 1866 page 800.), namely, that a Peach-almond, grafted on a peach, bore, during 1863 and 1864 almonds alone, but in 1865 bore six peaches and no almonds. M. Carriere, in commenting on this fact, cites the case of a double-flowered almond which, after producing during several years almonds, suddenly bore for two years in succession spherical fleshy peach-like fruits, but in 1865 reverted to its former state and produced large almonds.

Again, as I hear from Mr. Rivers, the double-flowering Chinese peaches resemble almonds in their manner of growth and in their flowers; the fruit is much elongated and flattened, with the flesh both bitter and sweet, but not uneatable, and it is said to be of better quality in China. From this stage one small step leads us to such inferior peaches as are occasionally raised from seed. For instance, Mr. Rivers sowed a number of peach-stones imported from the United States, where they are collected for raising stocks, and some of the trees raised by him produced peaches which were very like almonds in appearance, being small and hard, with the pulp not softening till very late in the autumn. Van Mons (10/28. Quoted in 'Journal de La Soc. Imp. d'Horticulture' 1855 page 238.) also states that he once raised from a peach-stone a peach having the aspect of a wild tree, with fruit like that of the almond. From inferior peaches, such as these just described, we may pass by small transitions, through clingstones of poor quality, to our best and most melting kinds. From this gradation, from the cases of sudden variation above recorded, and from the fact that the peach has not been found wild, it seems to me by far the most probable view, that the peach is the descendant of the almond, improved and modified in a marvellous manner.

One fact, however, is opposed to this conclusion. A hybrid, raised by Knight from the sweet almond by the pollen of the peach, produced flowers with little or no pollen, yet bore fruit, having been apparently fertilised by a neighbouring nectarine. Another hybrid, from a sweet almond by the pollen of a nectarine, produced during the first three years imperfect blossoms, but afterwards perfect flowers with an abundance of pollen. If this slight degree of sterility cannot be accounted for by the youth of the trees (and this often causes lessened fertility), or by the monstrous state of the flowers, or by the conditions to which the trees were exposed, these two cases would afford a good argument against the peach being the descendant of the almond.

Whether or not the peach has proceeded from the almond, it has certainly given rise to nectarines, or smooth peaches, as they are called by the French. Most of the varieties, both of the peach and nectarine, reproduce themselves truly by seed. Gallesio (10/29. 'Teoria della Riproduzione Vegetale' 1816 page 86.) says he has verified this with respect to eight races of the peach. Mr. Rivers (10/30. 'Gardener's Chronicle' 1862 page 1195.) has given some striking instances from his own experience, and it is notorious that good peaches are constantly raised in North America from seed. Many of the American sub-varieties come true or nearly true to their kind, such as the white-blossom, several of the yellow-fruited freestone peaches, the blood clingstone, the heath, and the lemon clingstone. On the other hand, a clingstone peach has been known to give rise to a freestone. (10/31. Mr. Rivers 'Gardener's Chronicle' 1859 page 774.) In England it has been noticed that seedlings inherit from their parents flowers of the same size and colour. Some characters, however, contrary to what might have been expected, often are not inherited; such as the presence and form of the glands on the leaves. (10/32. Downing 'The Fruits of America' 1845 pages 475, 489, 492, 494, 496. See also F. Michaux 'Travels in N. America' English translation page 228. For similar cases in France see Godron 'De l'Espece' tome 2 page 97.) With respect to nectarines, both cling and freestones are known in North America to reproduce themselves by seed. (10/33. Brickell 'Nat. Hist. of N. Carolina' page 102 and Downing 'Fruit Trees' page 505.) In England the new white nectarine was a seedling of the old white, and Mr. Rivers (10/34. 'Gardener's Chronicle' 1862 page 1196.) has recorded several similar cases. From this strong tendency to inheritance, which both peach and nectarine trees exhibit,—from certain slight constitutional differences (10/35. The peach and nectarine do not succeed equally well in the some soil: see Lindley 'Horticulture' page 351.) in their nature,—and from the great difference in their fruit both in appearance and flavour, it is not surprising, notwithstanding that the trees differ in no other respects and cannot even be distinguished, as I am informed by Mr. Rivers, whilst young, that they have been ranked by some authors as specifically distinct. Gallesio does not doubt that they are distinct; even Alph. De Candolle does not appear perfectly assured of their specific identity: and an eminent botanist has quite recently (10/36. Godron 'De l'Espece' tome 2 1859 page 97.) maintained that the nectarine "probably constitutes a distinct species."

Hence it may be worth while to give all the evidence on the origin of the nectarine. The facts in themselves are curious, and will hereafter have to be referred to when the important subject of bud-variation is discussed. It is asserted (10/37. 'Transact. Hort. Soc.' volume 6 page 394.) that the Boston nectarine was produced from a peach-stone, and this nectarine reproduced itself by seed. (10/38. Downing's 'Fruit Trees' page 502.) Mr. Rivers states (10/39. 'Gardener's Chronicle' 1862 page 1195.) that from stones of three distinct varieties of the peach he raised three varieties of nectarine; and in one of these cases no nectarine grew near the parent peach-tree. In another instance Mr. Rivers raised a nectarine from a peach, and in the succeeding generation another nectarine from this nectarine. (10/40. 'Journal of Horticulture' February 5, 1866 page 102.) Other such instances have been communicated to me, but they need not be given. Of the converse case, namely, of nectarine-stones yielding peach-trees (both free and clingstones), we have six undoubted instances recorded by Mr. Rivers; and in two of these instances the parent nectarines had been seedlings from other nectarines. (10/41. Mr. Rivers in 'Gardener's 'Chronicle' 1859 page 774, 1862 page 1195; 1865 page 1059; and 'Journal of Hort.' 1866 page 102.)

With respect to the more curious case of full-grown peach-trees suddenly producing nectarines by bud-variation (or sports as they are called by gardeners), the evidence is superabundant; there is also good evidence of the same tree producing both peaches and nectarines, or half-and-half fruit; by this term I mean a fruit with the one-half a perfect peach, and the other half a perfect nectarine.

Peter Collinson in 1741 recorded the first case of a peach-tree producing a nectarine (10/42. 'Correspondence of Linnaeus' 1821 pages 7, 8, 70.) and in 1766 he added two other instances. In the same work, the editor, Sir J.E. Smith, describes the more remarkable case of a tree in Norfolk which usually bore both perfect nectarines and perfect peaches; but during two seasons some of the fruit were half and half in nature.

Mr. Salisbury in 1808 (10/43. 'Transact. Hort. Soc.' volume 1 page 103.) records six other cases of peach-trees producing nectarines. Three of the varieties are named; viz., the Alberge, Belle Chevreuse, and Royal George. This latter tree seldom failed to produce both kinds of fruit. He gives another case of a half-and-half fruit.

At Radford in Devonshire (10/44. Loudon's 'Gardener's Mag.' 1826 volume 1. page 471.) a clingstone peach, purchased as the Chancellor, was planted in 1815, and in 1824, after having previously produced peaches alone, bore on one branch twelve nectarines; in 1825 the same branch yielded twenty-six nectarines, and in 1826 thirty-six nectarines, together with eighteen peaches. One of the peaches was almost as smooth on one side as a nectarine. The nectarines were as dark as, but smaller than, the Elruge.

At Beccles a Royal George peach (10/45. Loudon's 'Gardener's Mag.' 1828 page 53.) produced a fruit, "three parts of it being peach and one part nectarine, quite distinct in appearance as well as in flavour." The lines of division were longitudinal, as represented in the woodcut. A nectarine- tree grew five yards from this tree.

Professor Chapman states (10/46. Ibid 1830 page 597.) that he has often seen in Virginia very old peach-trees bearing nectarines.

A writer in the 'Gardener's Chronicle' says that a peach tree planted fifteen years previously (10/47. 'Gardener's Chronicle' 1841 page 617.) produced this year a nectarine between two peaches; a nectarine-tree grew close by.

In 1844 (10/48. 'Gardener's Chronicle' 1844 page 589.) a Vanguard peach- tree produced, in the midst of its ordinary fruit, a single red Roman nectarine.

Mr. Calver is stated (10/49. 'Phytologist' volume 4 page 299.) to have raised in the United States a seedling peach which produced a mixed crop of both peaches and nectarines.

Near Dorking (10/50. 'Gardener's Chronicle' 1856 page 531.) a branch of the Teton de Venus peach, which reproduces itself truly by seed (10/51. Godron, 'De l'Espece' tome 2 page 97.), bore its own fruit "so remarkable for its prominent point, and a nectarine rather smaller but well formed and quite round."

The previous cases all refer to peaches suddenly producing nectarines, but at Carclew (10/52. 'Gardener's Chronicle' 1856 page 531.) the unique case occurred, of a nectarine-tree, raised twenty years before from seed and never grafted, producing a fruit half peach and half nectarine; subsequently bore a perfect peach.

To sum up the foregoing facts; we have excellent evidence of peach-stones producing nectarine-trees, and of nectarine-stones producing peach-trees,— of the same tree bearing peaches and nectarines,—of peach-trees suddenly producing by bud-variation nectarines (such nectarines reproducing nectarines by seed), as well as fruit in part nectarine and in part peach,- -and, lastly, of one nectarine-tree first bearing half-and-half fruit, and subsequently true peaches. As the peach came into existence before the nectarine, it might have been expected from the law of reversion that nectarines would have given birth by bud-variation or by seed to peaches, oftener than peaches to nectarines; but this is by no means the case.

Two explanations have been suggested to account for these conversions. First, that the parent trees have been in every case hybrids (10/53. Alph. De Candolle 'Geograph. Bot.' page 886.) between the peach and nectarine, and have reverted by bud-variation or by seed to one of their pure parent forms. This view in itself is not very improbable; for the Mountaineer peach, which was raised by Knight from the red nutmeg-peach by pollen of the violette hative nectarine (10/54. Thompson in Loudon's 'Encyclop. of Gardening' page 911.), produces peaches, but these are said SOMETIMES to partake of the smoothness and flavour of the nectarine. But let it be observed that in the previous list no less than six well-known varieties and several unnamed varieties of the peach have once suddenly produced perfect nectarines by bud variation: and it would be an extremely rash supposition that all these varieties of the peach, which have been cultivated for years in many districts, and which show not a vestige of a mixed parentage, are, nevertheless, hybrids. A second explanation is, that the fruit of the peach has been directly affected by the pollen of the nectarine: although this certainly is possible, it cannot here apply; for we have not a shadow of evidence that a branch which has borne fruit directly affected by foreign pollen is so profoundly modified as afterwards to produce buds which continue to yield fruit of the new and modified form. Now it is known that when a bud on a peach-tree has once borne a nectarine the same branch has in several instances gone on during successive years producing nectarines. The Carclew nectarine, on the other hand, first produced half-and-half fruit, and subsequently pure peaches. Hence we may confidently accept the common view that the nectarine is a variety of the peach, which may be produced either by bud-variation or from seed. In the following chapter many analogous cases of bud-variation will he given.

The varieties of the peach and the nectarine run in parallel lines. In both classes the kinds differ from each other in the flesh of the fruit being white, red, or yellow; in being clingstones or freestones; in the flowers being large or small, with certain other characteristic differences; and in the leaves being serrated without glands, or crenated and furnished with globose or reniform glands. (10/55. 'Catalogue of Fruit in Garden of Hort. Soc.' 1842 page 105.) We can hardly account for this parallelism by supposing that each variety of the nectarine is descended from a corresponding variety of the peach; for though our nectarines are certainly the descendants of several kinds of peaches, yet a large number are the descendants of other nectarines, and they vary so much when thus reproduced that we can scarcely admit the above explanation.

The varieties of the peach have largely increased in number since the Christian era, when from two to five varieties were known (10/56. Dr. A. Targioni-Tozzetti 'Journal Hort. Soc.' volume 9 page 167. Alph. de Candolle 'Geograph. Bot.' page 885.) and the nectarine was unknown. At the present time, besides many varieties said to exist in China, Downing describes, in the United States, seventy-nine native and imported varieties of the peach; and a few years ago Lindley (10/57. 'Transact. Hort. Soc.' volume 5 page 554. See also Carriere 'Description et Class. des Varietes de Pechers.') enumerated one hundred and sixty-four varieties of the peach and nectarine grown in England. I have already indicated the chief points of difference between the several varieties. Nectarines, even when produced from distinct kinds of peaches, always possess their own peculiar flavour, and are smooth and small. Clingstone and freestone peaches, which differ in the ripe flesh either firmly adhering to the stone, or easily separating from it, also differ in the character of the stone itself; that of the freestones or melters being more deeply fissured, with the sides of the fissures smoother than in clingstones. In the various kinds the flowers differ not only in size, but in the larger flowers the petals are differently shaped, more imbricated, generally red in the centre and pale towards the margin: whereas in the smaller flowers the margin of the petal is usually more darkly coloured. One variety has nearly white flowers. The leaves are more or less serrated, and are either destitute of glands, or have globose or reniform glands (10/58. Loudon's 'Encyclop. of Gardening' page 907.) and some few peaches, such as the Brugnen, bear on the same tree both globular and kidney-shaped glands. (10/59. M. Carriere in 'Gardener's Chronicle' 1865 page 1154.) According to Robertson (10/60. 'Transact. Hort. Soc.' volume 3 page 332. See also 'Gardener's Chronicle' 1865 page 271 to same effect. Also 'Journal of Horticulture' September 26, 1865 page 254.) the trees with glandular leaves are liable to blister, but not in any great degree to mildew; whilst the non-glandular trees are more subject to curl, to mildew, and to the attacks of aphides. The varieties differ in the period of their maturity, in the fruit keeping well, and in hardiness,—the latter circumstance being especially attended to in the United States. Certain varieties, such as the Bellegarde, stand forcing in hot-houses better than other varieties. The flat-peach of China is the most remarkable of all the varieties; it is so much depressed towards the summit, that the stone is here covered only by roughened skin and not by a fleshy layer. (10/61. 'Transact. Hort. Soc.' volume 4 page 512.) Another Chinese variety, called the Honey-peach, is remarkable from the fruit terminating in a long sharp point; its leaves are glandless and widely dentate. (10/62. 'Journal of Horticulture' September 8, 1853 page 188.) The Emperor of Russia peach is a third singular variety, having deeply double-serrated leaves; the fruit is deeply cleft with one-half projecting considerably beyond the other: it originated in America, and its seedlings inherit similar leaves. (10/63. 'Transact. Hort. Soc.' volume 6 page 412.)

The peach has also produced in China a small class of trees valued for ornament, namely the double-flowered; of these, five varieties are now known in England, varying from pure white, through rose, to intense crimson. (10/64. 'Gardener's Chronicle' 1857 page 216.) One of these varieties, called the camellia-flowered, bears flowers above 2 1/4 inches in diameter, whilst those of the fruit-bearing kinds do not at most exceed 1 1/4 inch in diameter. The flowers of the double-flowered peaches have the singular property (10/65. 'Journal of Hort. Soc.' volume 2 page 283.) of frequently producing double or treble fruit. Finally, there is good reason to believe that the peach is an almond profoundly modified; but whatever its origin may have been, there can be no doubt that it has yielded during the last eighteen centuries many varieties, some of them strongly characterised, belonging both to the nectarine and peach form.

APRICOT (Prunus armeniaca).

It is commonly admitted that this tree is descended from a single species, now found wild in the Caucasian region. (10/66. Alph. de Candolle 'Geograph. Bot.' page 879.) On this view the varieties deserve notice, because they illustrate differences supposed by some botanists to be of specific value in the almond and plum. The best monograph on the apricot is by Mr. Thompson (10/67. 'Transact. Hort. Soc.' 2nd series volume 1 1835 page 56. See also 'Cat. of Fruit in Garden of Hort. Soc.' 3rd edition 1842.) who describes seventeen varieties. We have seen that peaches and nectarines vary in a strictly parallel manner; and in the apricot, which forms a closely allied genus, we again meet with variations analogous to those of the peach, as well as to those of the plum. The varieties differ considerably in the shape of their leaves, which are either serrated or crenated, sometimes with ear-like appendages at their bases, and sometimes with glands on the petioles. The flowers are generally alike, but are small in the Masculine. The fruit varies much in size, shape, and in having the suture little pronounced or absent; in the skin being smooth, or downy, as in the orange-apricot; and in the flesh clinging to the stone, as in the last-mentioned kind, or in readily separating from it, as in the Turkey- apricot. In all these differences we see the closest analogy with the varieties of the peach and nectarine. In the stone we have more important differences, and these in the case of the plum have been esteemed of specific value: in some apricots the stone is almost spherical, in others much flattened, being either sharp in front or blunt at both ends, sometimes channelled along the back, or with a sharp ridge along both margins. In the Moorpark, and generally in the Hemskirke, the stone presents a singular character in being perforated, with a bundle of fibres passing through the perforation from end to end. The most constant and important character, according to Thompson, is whether the kernel is bitter or sweet: yet in this respect we have a graduated difference, for the kernel is very bitter in Shipley's apricot; in the Hemskirke less bitter than in some other kinds; slightly bitter in the Royal; and "sweet like a hazel-nut" in the Breda, Angoumois, and others. In the case of the almond, bitterness has been thought by some high authorities to indicate specific difference.

In N. America the Roman apricot endures "cold and unfavourable situations, where no other sort, except the Masculine, will succeed; and its blossoms bear quite a severe frost without injury." (10/68. Downing 'The Fruits of America' 1845 page 157: with respect to the Alberge apricot in France see page 153.) According to Mr. Rivers (10/69. 'Gardener's Chronicle' 1863 page 364.), seedling apricots deviate but little from the character of their race: in France the Alberge is constantly reproduced from seed with but little variation. In Ladakh, according to Moorcroft (10/70. 'Travels in the Himalayan Provinces' volume 1 1841 page 295.) ten varieties of the apricot, very different from each other, are cultivated, and all are raised from seed, excepting one, which is budded.

PLUMS (Prunus insititia).

(FIGURE 43. PLUM STONES, of natural size, viewed laterally. 1. Bullace Plum. 2. Shropshire Damson. 3. Blue Gage. 4. Orleans. 5. Elvas. 6. Denyers Victoria. 7. Diamond.)

Formerly the sloe, P. spinosa, was thought to be the parent of all our plums; but now this honour is very commonly accorded to P. insititia or the bullace, which is found wild in the Caucasus and N.-Western India, and is naturalised in England. (10/71. See an excellent discussion on this subject in Hewett C. Watson 'Cybele Britannica' volume 4 page 80.) It is not at all improbable, in accordance with some observations made by Mr. Rivers (10/72. 'Gardener's Chronicle' 1865 page 27.), that both these forms, which some botanists rank as a single species, may be the parents of our domesticated plums. Another supposed parent-form, the P. domestica, is said to be found wild in the region of the Caucasus. Godron remarks (10/73. 'De l'Espece' tome 2 page 94. On the parentage of our plums see also Alph. De Candolle 'Geograph. Bot.' page 878. Also Targioni-Tozzetti 'Journal Hort. Soc.' volume 9 page 164. Also Babington 'Manual of Brit. Botany' 1851 page 87.) that the cultivated varieties may be divided into two main groups, which he supposes to be descended from two aboriginal stocks; namely, those with oblong fruit and stones pointed at both ends, having narrow separate petals and upright branches; and those with rounded fruit, with stones blunt at both ends, with rounded petals and spreading branches. From what we know of the variability of the flowers in the peach and of the diversified manner of growth in our various fruit-trees, it is difficult to lay much weight on these latter characters. With respect to the shape of the fruit, we have conclusive evidence that it is extremely variable: Downing (10/74. 'Fruits of America' pages 276, 278, 284, 310, 314. Mr. Rivers raised ('Gardener's Chronicle' 1863 page 27) from the Prune-peche, which bears large, round, red plums on stout, robust shoots, a seedling which bears oval, smaller fruit on shoots that are so slender as to be almost pendulous.) gives outlines of the plums of two seedlings, namely, the red and imperial gages, raised from the greengage; and the fruit of both is more elongated than that of the greengage. The latter has a very blunt broad stone, whereas the stone of the imperial gage is "oval and pointed at both ends." These trees also differ in their manner of growth: "the greengage is a very short- jointed, slow-growing tree, of spreading and rather dwarfish habit;" whilst its offspring, the imperial gage, "grows freely and rises rapidly, and has long dark shoots." The famous Washington plum bears a globular fruit, but its offspring, the emerald drop, is nearly as much elongated as the most elongated plum figured by Downing, namely, Manning's prune. I have made a small collection of the stones of twenty-five kinds, and they graduate in shape from the bluntest into the sharpest kinds. As characters derived from seeds are generally of high systematic importance, I have thought it worth while to give drawings of the most distinct kinds in my small collection; and they may be seen to differ in a surprising manner in size, outline, thickness, prominence of the ridges, and state of surface. It deserves notice that the shape of the stone is not always strictly correlated with that of the fruit: thus the Washington plum is spherical and depressed at the pole, with a somewhat elongated stone, whilst the fruit of the Goliath is more elongated, but the stone less so, than in the Washington. Again, Denyer's Victoria and Goliath bear fruit closely resembling each other, but their stones are widely different. On the other hand, the Harvest and Black Margate plums are very dissimilar, yet include closely similar stones.

The varieties of the plum are numerous, and differ greatly in size, shape, quality, and colour,—being bright yellow, green, almost white, blue, purple, or red. There are some curious varieties, such as the double or Siamese, and the Stoneless plum: in the latter the kernel lies in a roomy cavity surrounded only by the pulp. The climate of North America appears to be singularly favourable for the production of new and good varieties; Downing describes no less than forty, of which seven of first-rate quality have been recently introduced into England. (10/75. 'Gardener's Chronicle' 1855 page 726.) Varieties occasionally arise having an innate adaptation for certain soils, almost as strongly pronounced as with natural species growing on the most distinct geological formations; thus in America the imperial gage, differently from almost all other kinds, "is peculiarly fitted for DRY LIGHT soils where many sorts drop their fruit," whereas on rich heavy soils the fruit is often insipid. (10/76. Downing 'Fruit Trees' page 278.) My father could never succeed in making the Wine-Sour yield even a moderate crop in a sandy orchard near Shrewsbury, whilst in some parts of the same county and in its native Yorkshire it bears abundantly: one of my relations also repeatedly tried in vain to grow this variety in a sandy district in Staffordshire.

Mr. Rivers has given (10/77. 'Gardener's Chronicle' 1863 page 27. Sageret in his 'Pomologie Phys.' page 346 enumerates five kinds which can be propagated in France by seed: see also Downing 'Fruit Trees of America' page 305, 312, etc.) a number of interesting facts, showing how truly many varieties can be propagated by seed. He sowed the stones of twenty bushels of the greengage for the sake of raising stocks, and closely observed the seedlings; all had the smooth shoots, the prominent buds, and the glossy leaves of the greengage, but the greater number had smaller leaves and thorns." There are two kinds of damson, one the Shropshire with downy shoots, and the other the Kentish with smooth shoots, and these differ but slightly in any other respect: Mr. Rivers sowed some bushels of the Kentish damson, and all the seedlings had smooth shoots, but in some the fruit was oval, in others round or roundish, and in a few the fruit was small, and, except in being sweet, closely resembled that of the wild sloe. Mr. Rivers gives several other striking instances of inheritance: thus, he raised eighty thousand seedlings from the common German Quetsche plum, and "not one could be found varying in the least, in foliage or habit." Similar facts were observed with the Petite Mirabelle plum, yet this latter kind (as well as the Quetsche) is known to have yielded some well-established varieties; but, as Mr. Rivers remarks, they all belong to the same group with the Mirabelle.

CHERRIES (Prunus cerasus, avium, etc.).

Botanists believe that our cultivated cherries are descended from one, two, four, or even more wild stocks. (10/78. Compare Alph. De Candolle 'Geograph. Bot.' page 877. Bentham and Targioni-Tozzetti in 'Hort. Journal' volume 9 page 163; Godron 'De l'Espece' tome 2 page 92.) That there must be at least two parent species we may infer from the sterility of twenty hybrids raised by Mr. Knight from the morello fertilised by pollen of the Elton cherry; for these hybrids produced in all only five cherries, and one alone of these contained a seed. (10/79. 'Transact. Hort. Soc.' volume 5 1824 page 295.) Mr. Thompson (10/80. Ibid second series volume 1 1835 page 248.) has classified the varieties in an apparently natural method in two main groups by characters taken from the flowers, fruit, and leaves; but some varieties which stand widely separate in this classification are quite fertile when crossed; thus Knight's Early Black cherries are the product of a cross between two such kinds.

Mr. Knight states that seedling cherries are more variable than those of any other fruit-tree. (10/81. ) In the Catalogue of the Horticultural Society for 1842 eighty varieties are enumerated. Some varieties present singular characters: thus, the flower of the Cluster cherry includes as many as twelve pistils, of which the majority abort; and they are said generally to produce from two to five or six cherries aggregated together and borne on a single peduncle. In the Ratafia cherry several flower- peduncles arise from a common peduncle, upwards of an inch in length. The fruit of Gascoigne's Heart has its apex produced into a globule or drop; that of the white Hungarian Gean has almost transparent flesh. The Flemish cherry is "a very odd-looking fruit," much flattened at the summit and base, with the latter deeply furrowed, and borne on a stout, very short footstalk. In the Kentish cherry the stone adheres so firmly to the footstalk, that it could be drawn out of the flesh; and this renders the fruit well fitted for drying. The Tobacco-leaved cherry, according to Sageret and Thompson, produces gigantic leaves, more than a foot and sometimes even eighteen inches in length, and half a foot in breadth. The weeping cherry, on the other hand, is valuable only as an ornament, and, according to Downing, is "a charming little tree, with slender, weeping branches, clothed with small, almost myrtle-like foliage." There is also a peach-leaved variety.

Sageret describes a remarkable variety, LE GRIOTTIER DE LA TOUSSAINT, which bears at the same time, even as late as September, flowers and fruit of all degrees of maturity. The fruit, which is of inferior quality, is borne on long, very thin footstalks. But the extraordinary statement is made that all the leaf-bearing shoots spring from old flower-buds. Lastly, there is an important physiological distinction between those kinds of cherries which bear fruit on young or on old wood; but Sageret positively asserts that a Bigarreau in his garden bore fruit on wood of both ages. (10/82. These several statements are taken from the four following works, which may, I believe, be trusted: Thompson in 'Hort. Transact.' see above; Sageret 'Pomologie Phys.' 1830 pages 358, 364, 367, 379; 'Catalogue of the Fruit in the Garden of Hort. Soc.' 1842 pages 57, 60; Downing 'The Fruits of America' 1845 pages 189, 195, 200.)

APPLE (Pyrus malus).

The one source of doubt felt by botanists with respect to the parentage of the apple is whether, besides P. malus, two or three other closely allied wild forms, namely, P. acerba and praecox or paradisiaca, do not deserve to be ranked as distinct species. The P. praecox is supposed by some authors (10/83. Mr. Lowe states in his 'Flora of Madeira' quoted in 'Gardener's Chronicle' 1862 page 215 that the P. malus, with its nearly sessile fruit, ranges farther south than the long-stalked P. acerba, which is entirely absent in Madeira, the Canaries, and apparently in Portugal. This fact supports the belief that these two forms deserve to be called species. But the characters separating them are of slight importance, and of a kind known to vary in other cultivated fruit-trees.) to be the parent of the dwarf paradise stock, which, owing to the fibrous roots not penetrating deeply into the ground, is so largely used for grafting; but the paradise stocks, it is asserted (10/84. See 'Journ. of Hort. Tour, by Deputation of the Caledonian Hort. Soc.' 1823 page 459.) cannot be propagated true by seed. The common wild crab varies considerably in England; but many of the varieties are believed to be escaped seedlings. (10/85. H.C. Watson 'Cybele Britannica' volume 1 page 334.) Every one knows the great difference in the manner of growth, in the foliage, flowers, and especially in the fruit, between the almost innumerable varieties of the apple. The pips or seeds (as I know by comparison) likewise differ considerably in shape, size, and colour. The fruit is adapted for eating or for cooking in various ways, and keeps for only a few weeks or for nearly two years. Some few kinds have the fruit covered with a powdery secretion, called bloom, like that on plums; and "it is extremely remarkable that this occurs almost exclusively among varieties cultivated in Russia." (10/86. Loudon's 'Gardener's Mag.' volume 6 1830 page 83.) Another Russian apple, the white Astracan, possesses the singular property of becoming transparent, when ripe, like some sorts of crabs. The API ETOILE has five prominent ridges, hence its name; the API NOIR is nearly black: the TWIN CLUSTER PIPPIN often bears fruit joined in pairs. (10/87. See 'Catalogue of Fruit in Garden of Hort. Soc.' 1842 and Downing 'American Fruit Trees.') The trees of the several sorts differ greatly in their periods of leafing and flowering; in my orchard the COURT PENDU PLAT produces leaves so late, that during several springs I thought that it was dead. The Tiffin apple scarcely bears a leaf when in full bloom; the Cornish crab, on the other hand, bears so many leaves at this period that the flowers can hardly be seen. (10/88. Loudon's Gardener's Magazine' volume 4 1828 page 112.) In some kinds the fruit ripens in mid- summer; in others, late in the autumn. These several differences in leafing, flowering, and fruiting, are not at all necessarily correlated; for, as Andrew Knight has remarked (10/89. 'The Culture of the Apple' page 43. Van Mons makes the same remark on the pear 'Arbres Fruitiers' tome 2 1836 page 414.), no one can judge from the early flowering of a new seedling, or from the early shedding or change of colour of the leaves, whether it will mature its fruit early in the season.

The varieties differ greatly in constitution. It is notorious that our summers are not hot enough for the Newtown Pippin (10/90. Lindley's 'Horticulture' page 116. See also Knight on the Apple-Tree, in 'Transact. of Hort. Soc.' volume 6 page 229.), which is the glory of the orchards near New York; and so it is with several varieties which we have imported from the Continent. On the other hand, our Court of Wick succeeds well under the severe climate of Canada. The Caville rouge de Micoud occasionally bears two crops during the same year. The Burr Knot is covered with small excrescences, which emit roots so readily that a branch with blossom-buds may be stuck in the ground, and will root and bear a few fruit even during the first year. (10/91. Transact. Hort. Soc.' volume 1 1812 page 120.) Mr. Rivers has recently described (10/92. 'Journal of Horticulture' March 13, 1866 page 194.) some seedlings valuable from their roots running near the surface. One of these seedlings was remarkable from its extremely dwarfed size, "forming itself into a bush only a few inches in height." Many varieties are particularly liable to canker in certain soils. But perhaps the strangest constitutional peculiarity is that the Winter Majetin is not attacked by the mealy bug or coccus; Lindley (10/93. 'Transact. Hort. Soc.' volume 4 page 68. For Knight's case see volume 6 page 547. When the coccus first appeared in this country it is said (volume 2 page 163) that it was more injurious to crab-stocks than to the apples grafted on them. The Majetin apple has been found equally free of the coccus at Melbourne in Australia ('Gardener's Chronicle' 1871 page 1065). The wood of this tree has been there analysed, and it is said (but the fact seems a strange one) that its ash contained over 50 per cent of lime, while that of the crab exhibited not quite 23 per cent. In Tasmania Mr. Wade ('Transact. New Zealand Institute' volume 4 1871 page 431) raised seedlings of the Siberian Bitter Sweet for stocks, and he found barely one per cent of them attacked by the coccus. Riley shows ('Fifth Report on Insects of Missouri' 1873 page 87) that in the United States some varieties of apples are highly attractive to the coccus and others very little so. Turning to a very different pest, namely, the caterpillar of a moth (Carpocapsa pomonella), Walsh affirms ('The American Entomologist' April 1869 page 160) that the maiden-blush "is entirely exempt from apple-worms." So, it is said, are some few other varieties; whereas others are "peculiarly subject to the attacks of this little pest.") states that in an orchard in Norfolk infested with these insects the Majetin was quite free, though the stock on which it was grafted was affected: Knight makes a similar statement with respect to a cider apple, and adds that he only once saw these insects just above the stock, but that three days afterwards they entirely disappeared; this apple, however, was raised from a cross between the Golden Harvey and the Siberian Crab; and the latter, I believe, is considered by some authors as specifically distinct.

The famous St. Valery apple must not be passed over; the flower has a double calyx with ten divisions, and fourteen styles surmounted by conspicuous oblique stigmas, but is destitute of stamens or corolla. The fruit is constricted round the middle, and is formed of five seed-cells, surmounted by nine other cells. (10/94. 'Mem. de La Soc. Linn. de Paris' tome 3 1825 page 164; and Seringe 'Bulletin Bot.' 1830 page 117.) Not being provided with stamens, the tree requires artificial fertilisation; and the girls of St. Valery annually go to "faire ses pommes," each marking her own fruit with a ribbon; and as different pollen is used the fruit differs, and we here have an instance of the direct action of foreign pollen on the mother plant. These monstrous apples include, as we have seen, fourteen seed-cells; the pigeon-apple (10/95. Gardener's Chronicle' 1849 page 24.) on the other hand, has only four, instead of, as with all common apples, five cells; and this certainly is a remarkable difference.

In the catalogue of apples published in 1842 by the Horticultural Society, 897 varieties are enumerated; but the differences between most of them are of comparatively little interest, as they are not strictly inherited. No one can raise, for instance, from the seed of the Ribston Pippin, a tree of the same kind; and it is said that the "Sister Ribston Pippin" was a white semi-transparent, sour-fleshed apple, or rather large crab. (10/96. R. Thompson, in 'Gardener's Chronicle' 1850 page 788.) Yet it was a mistake to suppose that with most varieties the characters are not to a certain extent inherited. In two lots of seedlings raised from two well-marked kinds, many worthless crab-like seedlings will appear, but it is now known that the two lots not only usually differ from each other, but resemble to a certain extent their parents. We see this indeed in the several sub-groups of Russetts, Sweetings, Codlins, Pearmains, Reinettes, etc. (10/97. Sageret 'Pomologie Physiologique' 1830 page 263. Downing 'Fruit Trees' pages 130, 134, 139, etc. Loudon's 'Gardener's Mag.' volume 8 p. 317. Alexis Jordan 'De l'Origine des diverses Varietes' in 'Mem. de l'Acad. Imp. de Lyon' tome 2 1852 pages 95, 114. 'Gardener's Chronicle' 1850 pages 774, 788.), which are all believed, and many are known, to be descended from other varieties bearing the same names.

PEARS (Pyrus communis).

I need say little on this fruit, which varies much in the wild state, and to an extraordinary degree when cultivated, in its fruit, flowers, and foliage. One of the most celebrated botanists in Europe, M. Decaisne, has carefully studied the many varieties (10/98. 'Comptes Rendus' July 6, 1863.); although he formerly believed that they were derived from more than one species, he now thinks that all belong to one. He has arrived at this conclusion from finding in the several varieties a perfect gradation between the most extreme characters; so perfect is this gradation that he maintains it to be impossible to classify the varieties by any natural method. M. Decaisne raised many seedlings from four distinct kinds, and has carefully recorded the variations in each. Notwithstanding this extreme degree of variability, it is now positively known that many kinds reproduce by seed the leading characters of their race. (10/99. 'Gardener's Chronicle' 1856 page 804; 1857 page 820; 1862 page 1195.)

STRAWBERRIES (Fragaria).

This fruit is remarkable on account of the number of species which have been cultivated, and from their rapid improvement within the last fifty or sixty years. Let any one compare the fruit of one of the largest varieties exhibited at our Shows with that of the wild wood strawberry, or, which will be a fairer comparison, with the somewhat larger fruit of the wild American Virginian Strawberry, and he will see what prodigies horticulture has effected. (10/100. Most of the largest cultivated strawberries are the descendants of F. grandiflora or chiloensis, and I have seen no account of these forms in their wild state. Methuen's Scarlet (Downing 'Fruits' page 527) has "immense fruit of the largest size," and belongs to the section descended from F. virginiana; and the fruit of this species, as I hear from Prof. A. Gray, is only a little larger than that of F. vesca, or our common wood-strawberry.) The number of varieties has likewise increased in a surprisingly rapid manner. Only three kinds were known in France, in 1746, where this fruit was early cultivated. In 1766 five species had been introduced, the same which are now cultivated, but only five varieties of Fragaria vesca, with some sub-varieties, had been produced. At the present day the varieties of the several species are almost innumerable. The species consist of, firstly, the wood or Alpine cultivated strawberries, descended from F. vesca, a native of Europe and of North America. There are eight wild European varieties, as ranked by Duchesne, of F. vesca, but several of these are considered species by some botanists. Secondly, the green strawberries, descended from the European F. collina, and little cultivated in England. Thirdly, the Hautbois, from the European F. elatior. Fourthly, the Scarlets, descended from F. virginiana, a native of the whole breadth of North America. Fifthly, the Chili, descended from F. chiloensis, an inhabitant of the west coast of the temperate parts both of North and South America. Lastly, the pines or Carolinas (including the old Blacks), which have been ranked by most authors under the name of F. grandiflora as a distinct species, said to inhabit Surinam; but this is a manifest error. This form is considered by the highest authority, M. Gay, to be merely a strongly marked race of F. chiloensis. (10/101. 'Le Fraisier' par le Comte L. de Lambertye 1864 page 50.) These five or six forms have been ranked by most botanists as specifically distinct; but this may be doubted, for Andrew Knight (10/102. 'Transact. Hort. Soc.' volume 3 1820 page 207.) who raised no less than 400 crossed strawberries, asserts that the F. virginiana, chiloensis and grandiflora "may be made to breed together indiscriminately," and he found, in accordance with the principle of analogous variation, "that similar varieties could be obtained from the seeds of any one of them."

Since Knight's time there is abundant and additional evidence (10/103. See an account by Prof. Decaisne, and by others in 'Gardener's Chronicle' 1862 page 335 and 1858 page 172; and Mr. Barnet's paper in 'Hort. Soc. Transact.' volume 6 1826 page 170.) of the extent to which the American forms spontaneously cross. We owe indeed to such crosses most of our choicest existing varieties. Knight did not succeed in crossing the European wood-strawberry with the American Scarlet or with the Hautbois. Mr. Williams of Pitmaston, however, succeeded; but the hybrid offspring from the Hautbois, though fruiting well, never produced seed, with the exception of a single one, which reproduced the parent hybrid form. (10/104. 'Transact. Hort. Soc.' volume 5 1824 page 294.) Major R. Trevor Clarke informs me that he crossed two members of the Pine class (Myatt's B. Queen and Keen's Seedling) with the wood and hautbois, and that in each case he raised only a single seedling; one of these fruited, but was almost barren. Mr. W. Smith, of York, has raised similar hybrids with equally poor success. (10/105. 'Journal of Horticulture' December 30, 1862 page 779. See also Mr. Prince to the same effect ibid 1863 page 418.) We thus see (10/106. For additional evidence see 'Journal of Horticulture' December 9, 1862 page 721.) that the European and American species can with some difficulty be crossed; but it is improbable that hybrids sufficiently fertile to be worth cultivation will ever be thus produced. This fact is surprising, as these forms structurally are not widely distinct, and are sometimes connected in the districts where they grow wild, as I hear from Professor Asa Gray, by puzzling intermediate forms.

The energetic culture of the Strawberry is of recent date, and the cultivated varieties can in most cases be classed under some one of the above native stocks. As the American strawberries cross so freely and spontaneously, we can hardly doubt that they will ultimately become inextricably confused. We find, indeed, that horticulturists at present disagree under which class to rank some few of the varieties; and a writer in the 'Bon Jardinier' of 1840 remarks that formerly it was possible to class all of them under some one species, but that now this is quite impossible with the American forms, the new English varieties having completely filled up the gaps between them. (10/107. 'Le Fraisier' par le Comte L. de Lambertye pages 221, 230.) The blending together of two or more aboriginal forms, which there is every reason to believe has occurred with some of our anciently cultivated productions, we see now actually occurring with our strawberries.

The cultivated species offer some variations worth notice. The Black Prince, a seedling from Keen's Imperial (this latter being a seedling of a very white strawberry, the white Carolina), is remarkable from "its peculiar dark and polished surface, and from presenting an appearance entirely unlike that of any other kind." (10/108. 'Transact. Hort. Soc.' volume 6 page 200.) Although the fruit in the different varieties differs so greatly in form, size, colour, and quality, the so-called seed (which corresponds with the whole fruit in the plum) with the exception of being more or less deeply embedded in the pulp, is, according to De Jonghe (10/109. 'Gardener's Chronicle' 1858 page 173.) absolutely the same in all: and this no doubt may be accounted for by the seed being of no value, and consequently not having been subjected to selection. The strawberry is properly three-leaved, but in 1761 Duchesne raised a single-leaved variety of the European wood-strawberry, which Linnaeus doubtfully raised to the rank of a species. Seedlings of this variety, like those of most varieties not fixed by long-continued selection, often revert to the ordinary form, or present intermediate states. (10/110. Godron 'De l'Espece' tome 1 page 161.) A variety raised by Mr. Myatt (10/111. 'Gardener's Chronicle' 1851 page 440.), apparently belonging to one of the American forms presents a variation of an opposite nature, for it has five leaves; Godron and Lambertye also mention a five-leaved variety of F. collina.

The Red Bush Alpine strawberry (one of the F. vesca section) does not produce stolons or runners, and this remarkable deviation of structure is reproduced truly by seed. Another sub-variety, the White Bush Alpine, is similarly characterised, but when propagated by seed it often degenerates and produces plants with runners. (10/112. F. Gloede in 'Gardener's Chronicle' 1862 page 1053.) A strawberry of the American Pine section is also said to make but few runners. (10/113. Downing 'Fruits' page 532.)

Much has been written on the sexes of strawberries; the true Hautbois properly bears the male and female organs on separate plants (10/114. Barnet in 'Hort. Transact.' volume 6 page 210.), and was consequently named by Duchesne dioica; but it frequently produces hermaphrodites; and Lindley (10/115. 'Gardener's Chronicle' 1847 page 539.), by propagating such plants by runners, at the same time destroying the males, soon raised a self- prolific stock. The other species often showed a tendency towards an imperfect separation of the sexes, as I have noticed with plants forced in a hot-house. Several English varieties, which in this country are free from any such tendency, when cultivated in rich soils under the climate of North America (10/116. For the several statements with respect to the American strawberries see Downing 'Fruits' page 524; 'Gardener's Chronicle' 1843 page 188; 1847 page 539; 1861 page 717.) commonly produce plants with separate sexes. Thus a whole acre of Keen's Seedlings in the United States has been observed to be almost sterile from the absence of male flowers; but the more general rule is, that the male plants overrun the females. Some members of the Cincinnati Horticultural Society, especially appointed to investigate this subject, report that "few varieties have the flowers perfect in both sexual organs," etc. The most successful cultivators in Ohio plant for every seven rows of "pistillata," or female plants, one row of hermaphrodites, which afford pollen for both kinds; but the hermaphrodites, owing to their expenditure in the production of pollen, bear less fruit than the female plants.

The varieties differ in constitution. Some of our best English kinds, such as Keen's Seedlings, are too tender for certain parts of North America, where other English and many American varieties succeed perfectly. That splendid fruit, the British Queen, can be cultivated but in few places either in England or France: but this apparently depends more on the nature of the soil than on the climate; a famous gardener says that "no mortal could grow the British Queen at Shrubland Park unless the whole nature of the soil was altered." (10/117. Mr. D. Beaton in 'Cottage Gardener' 1860 page 86. See also 'Cottage Gardener' 1855 page 88 and many other authorities. For the Continent see F. Gloede in 'Gardener's Chronicle' 1862 page 1053.) La Constantine is one of the hardiest kinds, and can withstand Russian winters, but it is easily burnt by the sun, so that it will not succeed in certain soils either in England or the United States. (10/118. Rev. W.F. Radclyffe in 'Journal of Hort.' March 14, 1865 page 207.) The Filbert Pine Strawberry "requires more water than any other variety; and if the plants once suffer from drought, they will do little or no good afterwards." (10/119. Mr. H. Doubleday in 'Gardener's Chronicle' 1862 page 1101.) Cuthill's Black Prince Strawberry evinces a singular tendency to mildew; no less than six cases have been recorded of this variety suffering severely, whilst other varieties growing close by, and treated in exactly the same manner, were not at all infested by this fungus. (10/120. 'Gardener's Chronicle' 1854 page 254.) The time of maturity differs much in the different varieties: some belonging to the wood or alpine section produce a succession of crops throughout the summer.

GOOSEBERRY (Ribes grossularia).

No one, I believe, has hitherto doubted that all the cultivated kinds are sprung from the wild plant bearing this name, which is common in Central and Northern Europe; therefore it will be desirable briefly to specify all the points, though not very important, which have varied. If it be admitted that these differences are due to culture, authors perhaps will not be so ready to assume the existence of a large number of unknown wild parent- stocks for our other cultivated plants. The gooseberry is not alluded to by writers of the classical period. Turner mentions it in 1573, and Parkinson specifies eight varieties in 1629; the Catalogue of the Horticultural Society for 1842 gives 149 varieties, and the lists of the Lancashire nurserymen are said to include above 300 names. (10/121. Loudon's 'Encyclop. of Gardening' page 930; and Alph. De Candolle 'Geograph. Bot.' page 910.) In the 'Gooseberry Grower's Register' for 1862 I find that 243 distinct varieties have won prizes at various periods, so that a vast number must have been exhibited. No doubt the difference between many of the varieties is very small; but Mr. Thompson in classifying the fruit for the Horticultural Society found less confusion in the nomenclature of the gooseberry than of any other fruit, and he attributes this "to the great interest which the prize-growers have taken in detecting sorts with wrong names," and this shows that all the kinds, numerous as they are, can be recognised with certainty.

The bushes differ in their manner of growth, being erect, or spreading, or pendulous. The periods of leafing and flowering differ both absolutely and relatively to each other; thus the Whitesmith produces early flowers, which from not being protected by the foliage, as it is believed, continually fail to produce fruit. (10/122. Loudon's 'Gardener's Magazine' volume 4 1828 page 112.) The leaves vary in size, tint, and in depth of lobes; they are smooth, downy, or hairy on the upper surface. The branches are more or less downy or spinose; "the Hedgehog has probably derived its name from the singular bristly condition of its shoots and fruit." The branches of the wild gooseberry, I may remark, are smooth, with the exception of thorns at the bases of the buds. The thorns themselves are either very small, few and single, or very large and triple; they are sometimes reflexed and much dilated at their bases. In the different varieties the fruit varies in abundance, in the period of maturity, in hanging until shrivelled, and greatly in size, "some sorts having their fruit large during a very early period of growth, whilst others are small, until nearly ripe." The fruit varies also much in colour, being red, yellow, green, and white—the pulp of one dark-red gooseberry being tinged with yellow; in flavour; in being smooth or downy,—few, however, of the Red gooseberries, whilst many of the so-called Whites, are downy; or in being so spinose that one kind is called Henderson's Porcupine. Two kinds acquire when mature a powdery bloom on their fruit. The fruit varies in the thickness and veining of the skin, and, lastly, in shape, being spherical, oblong, oval, or obovate. (10/123. The fullest account of the gooseberry is given by Mr. Thompson in 'Transact. Hort. Soc.' volume 1 2nd series 1835 page 218 from which most of the foregoing facts are taken.)

I cultivated fifty-four varieties, and, considering how greatly the fruit differs, it was curious how closely similar the flowers were in all these kinds. In only a few I detected a trace of difference in the size or colour of the corolla. The calyx differed in a rather greater degree, for in some kinds it was much redder than in others; and in one smooth white gooseberry it was unusually red. The calyx also differed in the basal part being smooth or woolly, or covered with glandular hairs. It deserves notice, as being contrary to what might have been expected from the law of correlation, that a smooth red gooseberry had a remarkably hairy calyx. The flowers of the Sportsman are furnished with very large coloured bracteae; and this is the most singular deviation of structure which I have observed. These same flowers also varied much in the number of the petals, and occasionally in the number of the stamens and pistils; so that they were semi-monstrous in structure, yet they produced plenty of fruit. Mr. Thompson remarks that in the Pastime gooseberry "extra bracts are often attached to the sides of the fruit." (10/124. 'Catalogue of Fruits of Hort. Soc. Garden' 3rd edition 1842.)

The most interesting point in the history of the gooseberry is the steady increase in the size of the fruit. Manchester is the metropolis of the fanciers, and prizes from five shillings to five or ten pounds are yearly given for the heaviest fruit. The 'Gooseberry Growers Register' is published annually; the earliest known copy is dated 1786, but it is certain that meetings for the adjudication of prizes were held some years previously. (10/125. Mr. Clarkson of Manchester on the Culture of the Gooseberry in Loudon's 'Gardener's Magazine' volume 4 1828 page 482.) The 'Register' for 1845 gives an account of 171 Gooseberry Shows, held in different places during that year; and this fact shows on how large a scale the culture has been carried on. The fruit of the wild gooseberry is said (10/126. Downing 'Fruits of America' page 213.) to weigh about a quarter of an ounce or 5 dwts., that is, 120 grains; about the year 1786 gooseberries were exhibited weighing 10 dwts., so that the weight was then doubled; in 1817 26 dwts. 17 grs. was attained; there was no advance till 1825, when 31 dwts. 16 grs. was reached; in 1830 "Teazer" weighed 32 dwts. 13 grs.; in 1841 "Wonderful" weighed 32 dwts. 16 grs.; in 1844 "London" weighed 35 dwts. 12 grs., and in the following year 36 dwts. 16 grs.; and in 1852 in Staffordshire, the fruit of the same variety reached the astonishing weight of 37 dwts. 7 grs. (10/127. 'Gardener's Chronicle' 1844 page 811 where a table is given; and 1845 page 819. For the extreme weights gained see 'Journal of Horticulture' July 26, 1864 page 61.) or 896 grs.; that is, between seven or eight times the weight of the wild fruit. I find that a small apple, 6 1/2 inches in circumference, has exactly this same weight. The "London" gooseberry (which in 1852 had altogether gained 333 prizes) has, up to the present year of 1875, never reached a greater weight than that attained in 1852. Perhaps the fruit of the gooseberry has now reached the greatest possible weight, unless in the course of time some new and distinct variety shall arise.

This gradual, and on the whole steady increase of weight from the latter part of the last century to the year 1852, is probably in large part due to improved methods of cultivation, for extreme care is now taken; the branches and roots are trained, composts are made, the soil is mulched, and only a few berries are left on each bush (10/128. Mr. Saul of Lancaster in Loudon's 'Gardener's Mag.' volume 3 1828 page 421; and volume 10 1834 page 42.) but the increase no doubt is in main part due to the continued selection of seedlings which have been found to be more and more capable of yielding such extraordinary fruit. Assuredly the "Highwayman" in 1817 could not have produced fruit like that of the "Roaring Lion" in 1825; nor could the "Roaring Lion," though it was grown by many persons in many places, gain the supreme triumph achieved in 1852 by the "London" Gooseberry.

WALNUT (Juglans regia).

This tree and the common nut belong to a widely different order from the foregoing fruits, and are therefore here noticed. The walnut grows wild on the Caucasus and in the Himalaya, where Dr. Hooker (10/129. 'Himalayan Journals' 1854 volume 2 page 334. Moorcroft 'Travels' volume 2 page 146 describes four varieties cultivated in Kashmir.) found the fruit of full size, but "as hard as a hickory-nut." It has been found fossil, as M. de Saporta informs me, in the tertiary formation, of France.

In England the walnut presents considerable differences, in the shape and size of the fruit, in the thickness of the husk, and in the thinness of the shell; this latter quality has given rise to a variety called the thin- shelled, which is valuable, but suffers from the attacks of titmice. (10/130. 'Gardener's Chronicle' 1850 page 723.) The degree to which the kernel fills the shell varies much. In France there is a variety called the Grape or cluster-walnut, in which the nuts grow in "bunches of ten, fifteen, or even twenty together." There is another variety which bears on the same tree differently shaped leaves, like the heterophyllous hornbeam; this tree is also remarkable from having pendulous branches, and bearing elongated, large, thin-shelled nuts. (10/131. Paper translated in Loudon's 'Gardener's Mag.' 1829 volume 5 page 202.) M. Cardan has minutely described (10/132. Quoted in 'Gardener's Chronicle' 1849 page 101.) some singular physiological peculiarities in the June-leafing variety, which produces its leaves and flowers four or five weeks later than the common varieties; and although in August it is apparently in exactly the same state of forwardness as the other kinds, it retains its leaves and fruit much later in the autumn. These constitutional peculiarities are strictly inherited. Lastly, walnut-trees, which are properly monoicous, sometimes entirely fail to produce male flowers. (10/133. 'Gardener's Chronicle' 1847 pages 541 and 558.)

NUTS (Corylus avellana).

Most botanists rank all the varieties under the same species, the common wild nut. (10/134. The following details are taken from the 'Catalogue of Fruits, 1842 in Garden of Hort. Soc.' page 103; and from Loudon's 'Encyclop. of Gardening' page 943.) The husk, or involucre, differs greatly, being extremely short in Barr's Spanish, and extremely long in filberts, in which it is contracted so as to prevent the nut falling out. This kind of husk also protects the nut from birds, for titmice (Parus) have been observed (10/135. 'Gardener's Chron.' 1860 page 956.) to pass over filberts, and attack cobs and common nuts growing in the same orchard. In the purple-filbert the husk is purple, and in the frizzled-filbert it is curiously laciniated; in the red-filbert the pellicle of the kernel is red. The shell is thick in some varieties, but is thin in Cosford's-nut, and in one variety is of a bluish colour. The nut itself differs much in size and shape, being ovate and compressed in filberts, nearly round and of great size in cobs and Spanish nuts, oblong and longitudinally striated in Cosford's, and obtusely four-sided in the Downton Square nut.

CUCURBITACEOUS PLANTS.

These plants have been for a long period the opprobrium of botanists; numerous varieties have been ranked as species, and, what happens more rarely, forms which now must be considered as species have been classed as varieties. Owing to the admirable experimental researches of a distinguished botanist, M. Naudin (10/136. 'Annales des Sc. Nat. Bot.' 4th series volume 6 1856 page 5.), a flood of light has recently been thrown on this group of plants. M. Naudin, during many years, observed and experimented on above 1200 living specimens, collected from all quarters of the world. Six species are now recognised in the genus Cucurbita; but three alone have been cultivated and concern us, namely, C. maxima and pepo, which include all pumpkins, gourds, squashes, and the vegetable marrow, and C. moschata. These three species are not known in a wild state; but Asa Gray (10/137. 'American Journ. of Science' 2nd series volume 24 1857 page 442.) gives good reason for believing that some pumpkins are natives of N. America.

These three species are closely allied, and have the same general habit, but their innumerable varieties can always be distinguished, according to Naudin, by certain almost fixed characters; and what is still more important, when crossed they yield no seed, or only sterile seed; whilst the varieties spontaneously intercross with the utmost freedom. Naudin insists strongly (page 15), that, though these three species have varied greatly in many characters, yet it has been in so closely an analogous manner that the varieties can he arranged in almost parallel series, as we have seen with the forms of wheat, with the two main races of the peach, and in other cases. Though some of the varieties are inconstant in character, yet others, when grown separately under uniform conditions of life, are, as Naudin repeatedly (pages 6, 16, 35) urges, "douees d'une stabilite presque comparable a celle des especes les mieux caracterisees." One variety, l'Orangin (pages 43, 63), has such prepotency in transmitting its character, that when crossed with other varieties a vast majority of the seedlings come true. Naudin, referring (page 47) to C. pepo, says that its races "ne different des especes veritables qu'en ce qu'elles peuvent s'allier les unes aux autres par voie d'hybridite, sans que leur descendance perde la faculte de se perpetuer." If we were to trust to external differences alone, and give up the test of sterility, a multitude of species would have to be formed out of the varieties of these three species of Cucurbita. Many naturalists at the present day lay far too little stress, in my opinion, on the test of sterility; yet it is not improbable that distinct species of plants after a long course of cultivation and variation may have their mutual sterility eliminated, as we have every reason to believe has occurred with domesticated animals. Nor, in the case of plants under cultivation, should we be justified in assuming that varieties never acquire a slight degree of mutual sterility, as we shall more fully see in a future chapter when certain facts are given on the high authority of Gartner and Kolreuter. (10/138. Gartner 'Bastarderzeugung' 1849 s. 87 and s. 169 with respect to Maize; on Verbascum ibid s. 92 and 181; also his 'Kenntniss der Befruchtung' s. 137. With respect to Nicotiana see Kolreuter 'Zweite Forts.' 1764 s. 53; though this is a somewhat different case.)

The forms of C. pepo are classed by Naudin under seven sections, each including subordinate varieties. He considers this plant as probably the most variable in the world. The fruit of one variety (pages 33, 46) exceeds in value that of another by more than two thousand fold! When the fruit is of very large size, the number produced is few (page 45); when of small size, many are produced. No less astonishing (page 33) is the variation in the shape of the fruit, the typical form apparently is egg-like, but this becomes either drawn out into a cylinder, or shortened into a flat disc. We have also an almost infinite diversity in the colour and state of surface of the fruit, in the hardness both of the shell and of the flesh, and in the taste of the flesh, which is either extremely sweet, farinaceous, or slightly bitter. The seeds also differ in a slight degree in shape, and wonderfully in size (page 34), namely, from six or seven to more than twenty-five millimetres in length.

In the varieties which grow upright or do not run and climb, the tendrils, though useless (page 31), are either present or are represented by various semi-monstrous organs, or are quite absent. The tendrils are even absent in some running varieties in which the stems are much elongated. It is a singular fact that (page 31) in all the varieties with dwarfed stems, the leaves closely resemble each other in shape.]

Those naturalists who believe in the immutability of species often maintain that, even in the most variable forms, the characters which they consider of specific value are unchangeable. To give an example from a conscientious writer (10/139. Godron 'De l'Espece' tome 2 page 64.) who, relying on the labours of M. Naudin, and referring to the species of Cucurbita, says, "au milieu de toutes les variations du fruit, les tiges, les feuilles, les calices, les corolles, les etamines restent invariables dans chacune d'elles." Yet M. Naudin, in describing Cucurbita pepo (page 30), says, "Ici, d'ailleurs, ce ne sont pas seulement les fruits qui varient, c'est aussi le feuillage et tout le port de la plante. Neanmoins, je crois qu'on la distinguera toujours facilement des deux autres especes, si l'on veut ne pas perdre de vue les caracteres differentiels que je m'efforce de faire ressortir. Ces caracteres sont quelquefois peu marques: il arrive meme que plusieurs d'entre eux s'effacent presque entierement, mais ii en reste toujours quelques-uns qui remettent l'observateur sur la voie." Now let it be noted what a difference, with regard to the immutability of the so- called specific characters this paragraph produces on the mind, from that above quoted from M. Godron.

I will add another remark: naturalists continually assert that no important organ varies; but in saying this they unconsciously argue in a vicious circle; for if an organ, let it be what it may, is highly variable, it is regarded as unimportant, and under a systematic point of view this is quite correct. But as long as constancy is thus taken as the criterion of importance, it will indeed be long before an important organ can be shown to be inconstant. The enlarged form of the stigmas, and their sessile position on the summit of the ovary, must be considered as important characters, and were used by Gasparini to separate certain pumpkins as a DISTINCT GENUS; but Naudin says (page 20), these parts have no constancy, and in the flowers of the Turban varieties of C. maxima they sometimes resume their ordinary structure. Again, in C. maxima, the carpels (page 19) which form the turban project even as much as two-thirds of their length out of the receptacle, and this latter part is thus reduced to a sort of platform; but this remarkable structure occurs only in certain varieties, and graduates into the common form in which the carpels are almost entirely enveloped within the receptacle. In C. moschata the ovarium (page 50) varies greatly in shape, being oval, nearly spherical, or cylindrical, more or less swollen in the upper part, or constricted round the middle, and either straight or curved. When the ovarium is short and oval the interior structure does not differ from that of C. maxima and pepo, but when it is elongated the carpels occupy only the terminal and swollen portion. I may add that in one variety of the cucumber (Cucumis sativus) the fruit regularly contains five carpels instead of three. (10/140. Naudin 'Annal. des Sc. Nat.' 4th series Bot. tome 11 1859 page 28.) I presume that it will not be disputed that we here have instances of great variability in organs of the highest physiological importance, and with most plants of the highest classificatory importance.

[Sageret (10/141. 'Memoire sur les Cucurbitacees' 1826 pages 6, 24.) and Naudin found that the cucumber (C. sativus) could not be crossed with any other species of the genus; therefore no doubt it is specifically distinct from the melon. This will appear to most persons a superfluous statement; yet we hear from Naudin (10/142. 'Flore des Serres' October 1861 quoted in 'Gardener's Chronicle' 1861 page 1135. I have often consulted and taken some facts from M. Naudin's Memoir on Cucumis in 'Annal. des Sc. Nat.' 4th series Bot. tome 11 1859 page 5.) that there is a race of melons, in which the fruit is so like that of the cucumber, "both externally and internally, that it is hardly possible to distinguish the one from the other except by the leaves." The varieties of the melon seem to be endless, for Naudin after six years' study had not come to the end of them: he divides them into ten sections, including numerous sub-varieties which all intercross with perfect ease. (10/143. See also Sageret 'Memoire' page 7.) Of the forms considered by Naudin to be varieties, botanists have made thirty distinct species! "and they had not the slightest acquaintance with the multitude of new forms which have appeared since their time." Nor is the creation of so many species at all surprising when we consider how strictly their characters are transmitted by seed, and how wonderfully they differ in appearance: "Mira est quidem foliorum et habitus diversitas, sed multo magis fructuum," says Naudin. The fruit is the valuable part, and this, in accordance with the common rule, is the most modified part. Some melons are only as large as small plums, others weigh as much as sixty-six pounds. One variety has a scarlet fruit! Another is not more than an inch in diameter, but sometimes more than a yard in length, "twisting about in all directions like a serpent." It is a singular fact that in this latter variety many parts of the plant, namely, the stems, the footstalks of the female flowers, the middle lobe of the leaves, and especially the ovarium, as well as the mature fruit, all show a strong tendency to become elongated. Several varieties of the melon are interesting from assuming the characteristic features of distinct species and even of distinct though allied genera: thus the serpent-melon has some resemblance to the fruit of Trichosanthes anguina; we have seen that other varieties closely resemble cucumbers; some Egyptian varieties have their seeds attached to a portion of the pulp, and this is characteristic of certain wild forms. Lastly, a variety of melon from Algiers is remarkable from announcing its maturity by "a spontaneous and almost sudden dislocation," when deep cracks suddenly appear, and the fruit falls to pieces; and this occurs with the wild C. momordica. Finally, M. Naudin well remarks that this "extraordinary production of races and varieties by a single species and their permanence when not interfered with by crossing, are phenomena well calculated to cause reflection."

USEFUL AND ORNAMENTAL TREES.

Trees deserve a passing notice on account of the numerous varieties which they present, differing in their precocity, in their manner of growth, their foliage, and bark. Thus of the common ash (Fraxinus excelsior) the catalogue of Messrs. Lawson of Edinburgh includes twenty-one varieties, some of which differ much in their bark; there is a yellow, a streaked reddish-white, a purple, a wart-barked and a fungous-barked variety. (10/144. Loudon's 'Arboretum et Fruticetum' volume 2 page 1217.) Of hollies no less than eighty-four varieties are grown alongside each other in Mr. Paul's nursery. (10/145. 'Gardener's Chronicle' 1866 page 1096.) In the case of trees, all the recorded varieties, as far as I can find out, have been suddenly produced by one single act of variation. The length of time required to raise many generations, and the little value set on the fanciful varieties, explains how it is that successive modifications have not been accumulated by selection; hence, also, it follows that we do not here meet with sub-varieties subordinate to varieties, and these again subordinate to higher groups. On the Continent, however, where the forests are more carefully attended to than in England, Alph. De Candolle (10/146. 'Geograph. Bot.' page 1096.) says that there is not a forester who does not search for seeds from that variety which he esteems the most valuable.

Our useful trees have seldom been exposed to any great change of conditions; they have not been richly manured, and the English kinds grow under their proper climate. Yet in examining extensive beds of seedlings in nursery-gardens considerable differences may be generally observed in them; and whilst touring in England I have been surprised at the amount of difference in the appearance of the same species in our hedgerows and woods. But as plants vary so much in a truly wild state, it would be difficult for even a skilful botanist to pronounce whether, as I believe to be the case, hedgerow trees vary more than those growing in a primeval forest. Trees when planted by man in woods or hedges do not grow where they would naturally be able to hold their place against a host of competitors, and are therefore exposed to conditions not strictly natural: even this slight change would probably suffice to cause seedlings raised from such trees to be variable. Whether or not our half-wild English trees, as a general rule, are more variable than trees growing in their native forests, there can hardly be a doubt that they have yielded a greater number of strongly-marked and singular variations of structure.

In manner of growth, we have weeping or pendulous varieties of the willow, ash, elm, oak, and yew, and other trees; and this weeping habit is sometimes inherited, though in a singularly capricious manner. In the Lombardy poplar, and in certain fastigiate or pyramidal varieties of thorns, junipers, oaks, etc., we have an opposite kind of growth. The Hessian oak (10/147. 'Gardener's Chronicle' 1842 page 36.), which is famous from its fastigiate habit and size, bears hardly any resemblance in general appearance to a common oak; "its acorns are not sure to produce plants of the same habit; some, however, turn out the same as the parent-tree." Another fastigiate oak is said to have been found wild in the Pyrenees, and this is a surprising circumstance; it generally comes so true by seed, that De Candolle considered it as specifically distinct. (10/148. Loudon's 'Arboretum et Fruticetum' volume 3 page 1731.) The fastigiate Juniper (J. suecica) likewise transmits its character by seed. (10/149. Ibid volume 4 page 2489.) Dr. Falconer informs me that in the Botanic Gardens at Calcutta the great heat caused apple-trees to become fastigiate; and we thus see the same result following from the effects of climate and from some unknown cause. (10/150. Godron 'De l'Espece' tome 2 page 91 describes four varieties of Robinia remarkable from their manner of growth.)