The occurrence, also, of different forms of placentation in different flowers on the same plant is no unusual thing in malformed flowers; thus, in double flowers of Saponaria officinalis I have met with sutural, parietal, and free central placentation in the same plant.[100]

Professor Babington describes in the 'Gardeners' Chronicle,' 1844, p. 557, a curious flower of Cerastium, in which, in addition to other changes, the five carpellary leaves "were partially turned in without touching the placenta, which bears a cluster of ovules, and is perfectly clear of all connection with those partitions" (fig. 51). See also Lindley, 'Veg. Kingdom,' p. 497.



M. Baillon[101] records flowers of Bunias, some with ovules on the margins of the carpels, others with a central branch bearing the ovules; hence he concludes very justly that no fair inference can be drawn from these facts as to the normal placentation of Cruciferae.

The same excellent observer has recorded the occurrence of free central placentation in malformed flowers of Trifolium repens.[102]

In malformed flowers of Digitalis the change from axile to parietal placentation may often be seen. Mr. Berkeley describes an instance of this nature where the placentas were strictly parietal, and therefore receded from the distinctive characters of the order, and approximated to those of Gesneraceae.

The same author alludes to certain changes in the same flower where two open carpels "were soldered together laterally, as was clear by the rudiments of two styles, the placenta being produced only at the two united edges, the outer margins remaining in the normal condition. This may possibly tend to the explanation of some cases of anomalous placentation, for the only indication of the true nature of the placentation is afforded by the two rudimentary styles, in the absence of which the spongy receptacle of the seeds must have been supposed to spring from the medial nerve."

In other cases the placentas were parietal above, but axile at the base of the capsule, a striking instance of the facility with which axile placentation becomes parietal, the change being here effected by the prolongation of the axis, and the formation on it of a second whorl of carpellary leaves.

In double flowers of Primulaceae similar alterations in the placentation may often be observed. I have seen in Primula sinensis sutural, parietal, axile, and free central placentation all on the same plant; nay, even in the same capsule the ovules may be attached in various ways, and transitions from one form of placentation to another are not infrequent. The late Professor E. Forbes describes[103] an instance of true foliar and true axile placentation in the same flower in Vinca minor.

These and many similar changes, which it is not necessary further to allude to, are not so much to be wondered at when it is borne in mind how slight an alteration suffices to produce a change in the mode of placentation, and how frequent is the production of adventitious buds or of foliar outgrowths, as may be seen in the sections relating to those subjects and to Substitutions.

It will be remembered, also, how, in certain natural orders, under ordinary circumstances, considerable diversity in placentation exists, according as the margins of the carpels are merely valvate or are infolded so as to reach the centre. Often this diversity is due merely to the changes that take place during growth; thus, the placentation of Caryophylleae, Cucurbitaceae, Papaveraceae, and many other orders, varies according to the age of the carpel, and if any stasis or arrest of development occurs the placentation becomes altered accordingly.

It is not necessary, in this place, to enter into the question whether the placenta is, in all cases whatsoever, a dependence of the axis, as Payer, Schleiden, and others, have maintained, or whether it be foliar in some cases, axial in others. This question must be decided by the organogenists; teratologically, however, there can be no doubt that ovules may be formed from both foliar and axial organs, and, moreover, that, owing to the variability above referred to, both in what are called natural and in what are deemed abnormal conditions, it can rarely happen that any safe inferences as to the normal or typical placentation of any family of plants can be drawn from exceptional or monstrous formations.

On the subject of placentation the following authors may be consulted:

R. Brown, 'Ann. Nat. Hist.,' 1843, vol. xi, 35. Brongniart, 'Ann. Sc. Nat.,' 1834, ser. 2. i, p. 308. Alph. De Candolle, 'Neue Denkschrift der Allg. Schweizer Gesellsch.,' Band v. 1841, p. 9. Duchartre, 'Ann. Sc. Nat.,' 3rd ser., 1844, vol. ii, p. 290. Ibid., 'Elem. Bot.,' p. 574; 'Rev. Bot.,' 1846-7, p. 213. Babington, 'Gard. Chron.,' 1844, p. 557. Lindley, 'Elements,' p. 89; 'Veg. King.,' pp. 313, 497, &c. Berkeley, 'Gard. Chron.,' 1850, p. 612. Unger, 'Nov. Act. Acad. Nat. Cur.,' 1850; and in Henfrey's, 'Bot. Gazette,' 1851, p. 70. Schleiden, 'Principles,' English edit., p. 385. Payer, 'Elem. Bot.,' pp. 196, 211, 224. Baillon, 'Adansonia.' iii, p. 310. tab. iv. Cramer, 'Bildungsabweichungen,' p. 20, &c. Clos, 'Ann. Sc. Nat.,' 5th ser., iii, 313, as well as any of the general treatises on botany. Reference may also be made to the chapters on Prolification and Substitutions (in the case of the carpels and ovules), and to the authorities therein cited.

FOOTNOTES:

[90] 'Tijdschr. voor. nat. Gesch.,' viii, 1841. tab. ii, p. 178.

[91] Communication to the Internat. Bot. Congress, Paris, 1867.

[92] 'Bot. Zeit.,' 1859, p. 117, tab. v.

[93] 'Ann. Sc. Nat.,' ser. 2, vol. iv, 1835, p. 143. tab. v.

[94] See Kirschleger, 'Flora.' 1844. p. 566 (Scabiosa).

[95] 'Bull. Acad. Belg.,' t. xvii. part ii, p. 387.

[96] 'Clos. Mem. Acad. Toulouse,' 5th ser., t. vi. pp. 51, 70.

[97] 'Bull. Acad. Roy. Belg.,' xviii. part ii, p. 505, and vol. xvii, part i, p. 196, and vol. xix. part i. p. 260.

[98] See also Schlechtendal, 'Bot. Zeit.,' iv, p. 804. Primula veris, partibus perigonii spirae in modum confluentibus.

[99] Seemann's 'Journal of Botany,' vol. v, 1867, p. 158.

[100] 'Journ. Linn. Soc.,' i, 1857, p. 161. c. xylog.

[101] 'Adansonia,' ii, 306.

[102] 'Adansonia,' iv, p. 70, t. i.

[103] Henfrey's 'Bot. Gazette,' i, 265.



CHAPTER II.

PROLIFICATION.

Moquin-Tandon and other writers have classed the production of buds in unwonted situations under the head of multiplication, but, as the altered arrangement is of graver import than the mere increase in number, it seems preferable to place these cases under this heading rather than under that of alterations of number.

The adventitious bud may be a leaf-bud or a flower-bud; it may occupy the centre of a flower, thus terminating the axis, or it may be axillary to some or other of its component parts, or, again, it may be extra-floral. In this last case the prolification is of the inflorescence, and is hardly distinguishable from multiplication or subdivision of the common flower-stalk. In accordance with these differences we have median, axillary, and extra-floral prolification, each admitting of subdivision into a leafy or a floral variety, according to the nature of the adventitious bud. Under the head of each variety certain special peculiarities are noticed, but it may here be advisable to add a few general remarks on the subject.

Axillary prolification is a much less frequent malformation than the median form. If only the number of orders and genera be reckoned, the truth of this statement will be scarcely recognised; but if individual cases could be estimated, the difference in frequency between the two would be very much more obvious. This may, perhaps, be explained by the fact that the branch has a greater tendency to grow in length than it has to develop buds from the axils of the leaves. The flower is admitted to be homologous with the branch, and it is also known that, up to a certain time, the branch-bud or leaf-bud and the flower-bud do not essentially differ.[104] At a later stage the difference between the two is manifested, not only in the altered form of the lateral organs in the flower-bud, but in the tendency to an arrest of growth, thus limiting the length of the central axial portion. Now, in prolified flowers the functions and, to a considerable extent, the appearance of a leaf-bud or of a branch are assumed, and with them the tendency to grow in length is developed. Median prolification, therefore, in this sense, is a further step in retrograde metamorphosis than is the axillary form. To grow in length, and to produce axillary buds, are alike attributes of the branch; but the former is much more frequently called into play than the latter; for the same reason, median prolification is more common than the axillary form. This is borne out by the frequency with which apostasis, or the separation of the floral whorls one from another, to a greater degree than usual, is met with in prolified flowers.

In both forms the adventitious growth is much more frequently a flower-bud or an inflorescence than a leaf-bud or a branch. This may be due to the position of the flowers on a portion of the stem of the plant especially devoted to the formation of flower-buds, to the more or less complete exclusion of leaf-buds, i.e. on the inflorescence. This conjecture is borne out by the comparative rarity with which prolification has been observed in flowers that are solitary in the axils of the ordinary leaves of the plant. If the lists of genera appended hereto be perused, it will be seen that nearly all the cases occur in genera where the inflorescence is distinctly separated from the other branches of the stem. In direct proportion, then, to the degree in which one region of the axis or certain branches of a plant are devoted to the formation of flower-buds to the exclusion of leaf-buds, is the frequency with which those flowers become affected with floral prolification.

Flowers produced upon indefinite inflorescences are liable to be affected with either form of prolification more frequently than those borne upon definite inflorescences. Prolification in both varieties is also more frequently met with in branched inflorescences than in those in which the flowers are sessile; but the degree of branching seems less material, inasmuch as this malformation is more commonly recorded as occurring in racemes than in the more branched panicles, &c. From the similar arrest of growth in length, in the case of the flower, to that which occurs in the stem in the case of definite inflorescence, it might have been expected that axillary prolification would be more frequent in plants having a cymose arrangement of their flowers than in those whose inflorescence is indefinite; such, however, is not the case. The reason for this may be sought for in the lengthening of the floral axis, so common in prolified flowers—a condition the reverse of that which happens in the case of definite inflorescence.

Median prolification occurs frequently in double flowers; the axillary variety, on the other hand, is most common in flowers whose lateral organs have assumed more or less of the condition of leaves. The other coincident changes are alluded to elsewhere or do not present useful points of comparison, and may therefore be passed over.

Prolification of the inflorescence.—This consists in the formation of leaf-buds or of an undue number of flower-buds on the inflorescence. It must be distinguished from virescence, or the mere green colour of the floral organs, and from chloranthy, in which all or the greater portion of the parts of the flower are replaced by leaves. Prolification is, in fact, a formation of supernumerary buds, leafy or floral, as the case may be, these buds being sessile or stalked, the ordinary buds being not necessarily changed. Prolification of the inflorescence, like the other varieties, admits of subdivision, not only according to the foliar or floral nature of the bud, but according to its position, terminal or median and lateral.

Terminal prolification of the inflorescence, whether leafy or floral, is hardly to be looked upon in the light of a malformation[105] seeing that a similar condition is so commonly met with normally, as in Epacris, Metrosideros, Bromelia, Eucomis, &c., wherein the leafy axis projects beyond the inflorescence proper; or as in Primula imperialis, in which plant, as also in luxuriant forms of P. sinensis, tier after tier of flowers are placed in succession above the primary umbel. Nevertheless, when we meet with such conditions in plants which, under ordinary circumstances, do not manifest them, we must consider them as coming under the domain of teratology.

Median foliar prolification of the inflorescence is frequently met with in Coniferae, and has of late attracted unwonted attention from the researches of Caspary, Baillon, and others, on the morphology of these plants. The scales and bracts of the cone in these abnormal specimens frequently afford transitional forms of the greatest value in enabling morphologists to comprehend the real nature of the floral structure. It would be irrelevant here to enter into this subject; suffice it merely to say that an examination of very numerous specimens of this kind, in the common larch and in Cryptomeria Japonica, has enabled me to verify nearly the whole of Caspary's observations. A similar prolongation of the axis occurred in some of the male catkins of Castanea vesca, each of which had a tuft of small leaves at their extremity. In the common marigold and in Lotus corniculatus I have also seen instances of this kind. Kirschleger[106] describes a tuft of leaves as occurring on the apex of the flowering spike after the maturation of the fruit in Plantago, and a similar growth frequently takes place in the common wallflower, in Antirrhinum majus, &c. In cases where a renewal of growth in the axis of inflorescence has taken place after the ripening of the fruit, the French botanists use the term recrudescence, but the growth in question by no means always occurs after the ripening of the fruit, but frequently before. Professor Braun cites the case of a specimen of Plantago lanceolata, in which the spike was surmounted by a tuft of leaves and roots, as well as a still more singular instance in Eryngium viviparum, in which not only did particular branches terminate in rosettes of leaves provided with roots, but similar growths proceeded from the heads of flowers themselves. Baron de Melicoq[107] gives a case in Primula variabilis, in which at the top of the flower-stalk, in the centre of six flowers, was placed a complete plant in miniature, having three leaves, from the axil of one of which proceeded a rudimentary flower. Mr. W. B. Jeffries also forwarded me a polyanthus (fig. 52) in which the peduncle was surmounted by a small plant, forming a crown above the ordinary flower-stalk, just as the crown of the pineapple surmounts that fruit. A similar instance was exhibited at the Scientific Committee of the Horticultural Society on July 11th, 1868, by Mr. Wilson Saunders; the species in this case was P. cortusoides. To Mr. R. Dean I am indebted for a similar proliferous cyclamen, which seems similar to one mentioned by Schlechtendal.[108] This author alludes to an analogous circumstance in the inflorescence of Cytisus nigricans, where, however, the change was not so great as in the preceding cases. The instances just cited all occur in plants having an indefinite form of inflorescence; but the production of a tuft of leaves or of a leafy shoot above or beyond the inflorescence is not confined to plants with this habit of growth, for Jacquin figures and describes an instance of this nature in the cymose flower-stems of a Sempervivum. "Hi racemi," says he, "ultra flores producuntur in ramos, foliosos duo bifidos qui tandem trium unciarum longitudinem adepti fuerunt."[109]



Median floral prolification of the inflorescence, wherein a new inflorescence projects beyond the primary one, is not uncommon in plants having their flowers arranged in close heads or umbels, as in the common wild celery and other Umbelliferae.[110] I have also met with it in Trifolium repens, in the umbellate variety of the common primrose, and in the scarlet geranium. Engelmann cites it in Triticum repens, Roeper in Euphorbia palustris.[111]

Lateral foliar prolification of the inflorescence is of more common occurrence than the preceding. I have met with it, amongst other plants, frequently in Brassica oleracea, Pelargonium zonale, SCABIOSA, BELLIS, and many other composites, also in Leguminosae, e.g. Lupinus, Trifolium, Coronilla, &c. Prof. Oliver forwarded me a specimen of Euphorbia geniculata in which, in addition to other changes, there was a series of stalked buds bearing tufts of green scales, but without any trace of stamens or pistil; these adventitious buds occurred within the ordinary involucre of the plant, between it and the stamens. The pistil was unaffected in some cases, while in some others it was entirely wanting, the gynophore being surmounted by a cup-like involucre, divided into three acutely pointed lobes, each with a midrib; these encircled a series of stalked involucels, as before, and among which were scattered a few stamens, some perfect, others partially frondescent.

In a specimen of Scrophularia nodosa examined by me one of the lateral buds on each of the cymes was represented, not by a flower, but by a tuft of leaves, the other buds being unchanged. As the inflorescence was much contracted in size, the appearance of the whole plant was greatly changed.

Many of the instances of so-called viviparous plants, e.g., Polygonum viviparum, may be cited under this head.[112] Many species of Allium, Lilium, Saxifraga, Begonia, Achimenes, normally produce leaf-buds or bulbs in the inflorescence; so, too, leafy shoots are sometimes found in Alisma natans, Juncus uliginosus, Chlorophytum Sternbergianum, &c. As an accidental occurrence, a similar thing has been noticed in Lychnis coronaria, Phaius grandifolius, Oncidium cebolleta, Epidendrum elongatum,[113] &c. &c.

Here, too, may be mentioned those cases wherein a leaf-bud is found upon the surface of the so-called inferior ovary; generally a leaf only is found, but a leaf-bud may also originate in this situation, and in either case the inference is that the ovary is, in part at least, made of the dilated and hollowed axis. Leaves may occasionally be found in this way on the so-called calyx-tube or on the inferior ovaries of roses, pears, apples, Pereskia, Crataegus tanacetifolia, &c.

The fruits of Opuntia Salmania and of O. fragilis ('Bull. Soc. Bot. France,' vol. i, p. 306; vol. v, p. 115) have been observed to form small fruit-like branches around their summits. This circumstance is more fully treated of in the succeeding chapter relating to Heterotaxy.

Lateral floral prolification of the inflorescence.—This, which is termed by Engelmann Ecblastesis foliorum sub floralium,[114] is much the most common of all these deviations, and it is met with in every degree, from the presence of a single supernumerary flower in the axil of a bract to the existence of a small cluster or panicle of such flowers.



It is common in the Anemone coronaria and hortensis, also in the common scarlet Pelargonium (fig. 53). It has been frequently recorded in Poterium sanguisorba, and in Sanguisorba officinalis, and is especially common in Umbelliferae, Dipsacaceae, and Compositae; a familiar illustration in the latter order is afforded by the hen-and-chicken daisy. In some species of Compositae, indeed, it is a normal and constant occurrence, while in other cases, such as Filago germanica, usually described as proliferous, there is not, strictly speaking, any prolification, for the branching of the stalk takes place below the inflorescence, and the branches originate from the axils of ordinary leaves, not from the floral leaves or bracts. Convolvulus Sepium is very commonly subject to the production of flower-buds from the axils of the floral leaves. The several species of Plantain (Plantago) seem very liable to this and similar changes. Schlechtendal[115] gives a summary of the various kinds of malformation affecting the inflorescence in Plantago, and divides them into five groups, as follows:—1st, bracteate, wherein the inferior bracts are quite leaf-like, as is frequently seen in Plantago major. 2nd, roseate; bracts leafy in tufts or rosettes, without flowers, as in the so-called rose plantain, common in old-fashioned gardens in this country. 3rd, polystachyate; spike-branched, bearing other spikes in the axils of the bracts, as in P. lanceolata, P. maritima, &c. 4th, proliferous, where the flower-stalk bears a rosette, a spike, or a head with other rosettes. 5th, paniculate, in which the inflorescence has become a much-branched pyramidal panicle, covered with little bracts, and with very rudimentary flowers.[116] The first two groups belong rather to frondescence of the bracts; but with regard to the whole of them it will easily be surmised that intermediate forms occur, linking one group to the other, and defying exact allocation in either. Thus, in the borders of richly cultivated fields in the neighbourhood of London I have frequently gathered specimens of Plantago major with a branched spike provided with large leafy bracts, the branches of the spike being but little less in diameter than the ordinary single spike. These specimens would therefore seem to be intermediate between Schlechtendal's bracteate and polystachyate divisions. Wigand[117] also describes an anomalous specimen of Plantago major similar to those just mentioned, but having small lateral spikes in place of large ones. The instance quoted from Professor Braun would fall under the roseate section, as would also that of Kirschleger, though we are expressly told that the tuft of leaves in this last case was not developed until after the ripening of the seed-vessel. One of the characters of the roseate group, according to Schlechtendal, is the absence of flowers, but most persons who have had the opportunity of watching the growth of the rose plantain must have observed the occasional production of flowers, sometimes stalked, in the axils of the leafy bracts, and at the same time have noticed that the internodes become elongated, so that an approach is made to the ordinary spike-like form of the inflorescence. The proliferous group would include such specimens as that of P. lanceolata mentioned by Dr. Johnston,[118] wherein were several spikes, some sessile, others stalked and pendent, the whole intermixed with leaves and disposed in a rose-like manner. I have myself gathered specimens of this nature, occurring in the same plant, at Shanklin, Isle of Wight (fig. 56).



It is rather singular that each species of Plantago seems to have its own perverse mode of growth; for instance, the bracteate, polystachyate and paniculate forms are almost exclusively confined to P. major, the roseate form to P. media, the proliferous form to P. lanceolata.

The instances wherein flower-buds originate from the surface of an inferior ovary, as in those cases where the top of the stem is dilated so as to form part of the fruit, would be properly classed under the head of prolification of the inflorescence. As, however, there is still some difference of opinion as to the correct morphological interpretation to be put on some of these cases, it has been thought better to include them under the head of heterotaxy than of prolification.



Some of the cases of prolification of the inflorescence resulting in a branching of an ordinarily simple inflorescence, as in Reseda luteola (fig. 57), might equally well be placed with fission or multiplication of the axile organs. Branched spikes of this character are not so common among Orchids as might be expected. Professor Reichenbach enumerates a few instances in the Report of the International Botanical Congress of London, 1866, p. 121, and the same author gives an illustration in his 'Orchidographia Europoea,' tab. 150.

In Grasses, as indeed in other plants with a spicate inflorescence, this change occurs not unfrequently. The common Ray Grass (Lolium) is especially subject to the change in question, and among cultivated cereals, maize and wheat occasionally show this tendency to subdivision. One variety of the latter grain is cultivated in hot countries under the name of Egyptian wheat—Triticum vulgare, var. compositum.

Prolification of the inflorescence has been most frequently observed in the following genera:

Leafy. Floral.

Ranunculaceae Ranunculus. Ranunculus! Anemone. Anemone. Cruciferae. *Brassica! Caryophyllaceae. Lychnis! Dianthus! Geraniaceae. *Pelargonium! *Pelargonium! Leguminosae. *Trifolium! Trifolium! Lotus! Lotus! Coronilla! Cytisus. Cytisus. Rosaceae. Poterium. *Pyrus! *Pyrus! *Crataegus! Crataegus! *Rosa. Rosa! Sanguisorba.

Philadelphaceae. Philadelphus. Crassulaceae. Sempervivum. Echeveria. Crassula. Ficoideae. ?Tetragonia. Cactaceae. Opuntia. Opuntia. Pereskia. Saxifragaceae. Saxifraga! Umbelliferae. Seseli. *Apium! Cnidium. Chaerophyllum. Eryngium. Eryngium. Silaus. Heracleum! Heracleum! Hydrocotyle. Hydrocotyle. Daucus. Carum. Selinum. Angelica! Conium. Astrantia. OEnanthe. OEnanthe. Begoniaceae. Begonia! Valerianaceae. Valeriana. Dipsacaceae. *Scabiosa! *Scabiosa! Knautia! Knautia! Compositae. *Bellis! Centaurea. Calendula. Calendula. Anthemis. Coreopsis. Apargia. Lampsana. Carlina. Arnoseris. Tragopogon! Tragopogon! Rudbeckia! Senecio! Carlina. Bidens! Pyrethrum. Filago. Hedypnois. Cirsium. Lactuca. Campanulaceae. Prismatocarpus. Lobeliaceae. Jasione. Ericaceae. Azalea! Convolvulaceae. Convolvulus! Convolvulus! Calystegia! Scrophulariaceae. Scrophularia! Antirrhinum! Gesneraceae. Achimenes! Primulaceae. Primula! Primula! Cyclamen! Cyclamen! Plumbaginaceae. Armeria. Plantaginaceae. *Plantago! *Plantago! Polygonaceae. Polygonum! Euphorbiaceae. Euphorbia! Urticaceae. Ficus. Amentaceae. Corylus! Castanea! Castanea. Coniferae. *Larix! *Cryptomeria! Taxodium! Pinus. Orchidaceae. Phaius! Ophrys! Epidendrum! Oncidium! Liliaceae. *Allium! *Ornithogalum! *Lilium! Amaryllidaceae. Fourcroya Alismaceae. Alisma! Palmaceae. Cocos. Juncaceae. *Juncus! Restiaceae. Restio! Restio! Elegia! Elegia! Willdenovia! Willdenovia! Cyperaceae. Carex. Graminaceae. Dactylis. *Lolium! Festuca. *Zea! *Triticum! *Hordeum! Secale. Phleum.

In addition to the papers already cited the following works may be consulted with reference to prolification of the inflorescence:

Moquin-Tandon. 'El. Ter. Veg.,' p. 376. Engelmann, 'De Antholysi,' Secs. 85-87. Fleischer, 'Missbild. Versch. Cultur. Pflanz.' For figures of Hen and Chicken Daisy (Bellis prolifera). see Lobel, 'Ic.,' 477. Sweert, 'Florileg.,' pl. 98, f. 5. 'Hort. Eystett. Plant. Vern.,' fol. iv, f. i. &c. For similar malformations in marigold (Calendula), see Lobel, 'Ic.,' 553. 'Act. Acad. Nat. Cur.,' vol. x, p. 208. Jaeger, 'Missbilld.,' 192-195. 'Hort. Eystett.,' pl. aestiv. fol. iii, f. i. Klinsmann, 'Linnaea,' t. x, p. 607.

For monstrous plantains, in addition to previous citations, see Camerarius, 'Epist.,' p. 261, P. rosea. Matthioli, 'Krauterb,' 245. Lobel, 'Stirp. Advers. Nov.,' p. 128, P. major paniculata. J. Bauhin, 'Hist. Plant.,' i, p. 503 b. Ibid., p. 503, a, c, P. major rosea, bracteata paniculata, prolifera, &c. 'Hort. Eystett.,' pl. aestiv., t. vii, f. 2, P. rosea et P. bracteata. Lobel, 'Stirp. Hist.,' p. 162. Dodonaeus, 'Pempt.,' 1-4, cap. xxiii, P. major spica multiplex, i.e. paniculata. Gerard, 'Herbal.' Clusius, 'Plant. Rar. Hist.,' lib. v, p. 109-10, Plantago augustifolia Gareti prolifera. Marchand, 'Adansonia,' iv, p. 156.

Coniferae.—Richard, 'Mem. Conif.,' tab. xiii, f. 9. A. Braun, 'Das Individ.,' 1853, p. 65. De Cand., 'Organogr.,' tab. xxxvi. Wigand, 'Bot. Untersuch.,' 154. Schlechtendal, 'Bot. Zeit.,' 1859, p. 239. Caspary, 'De Abiet. flor. fem. struct. morphol.' Parlatore, 'Ann. Sc. Nat.,' 1862, vol. xvi, p. 215. Cramer, 'Bildungsabweich.,' p. 4, &c., &c.

Gramineae.—Bauhin, 'Pinax.,' 21. Morison, 'Hist. Plant.,' t. i. Winckler, 'Ephem. Nat. Cur.,' dec. i, ann. 7, 8, p. 151. Irmisch, 'Flora,' 1858, p. 40, &c.

See also under Chloranthy, Viviparous plants, &c.

Prolification of the flower.—In the preceding sections the formation of adventitious buds of a leafy or floral nature on the inflorescence has been considered. A similar production of buds may take place in the flower itself, either from its centre or from the axil of some of its constituent parts. Prolification of the flower is therefore median or axillary, and the adventitious bud itself may be of a leafy or a floral nature.

Median leafy prolification.—In this malformation the centre of the flower is occupied by a bud or a branch; the growing point or termination of the axis which ordinarily ceases to grow after the formation of the carpels, takes on new growth. This is well shown in the accompanying illustration (fig. 58), representing the thalamus of a strawberry prolonged beyond the fruits into a small leaf-bearing branch.



In other cases the carpels are entirely absent and their place is supplied by a leafy shoot as in a species of Verbascum, which came under my own observation. In this case the petals were virescent, and the stamens and pistils were entirely absent, hence in truth, the so-called flower more nearly resembled a branch. In a flower of a May Duke cherry, for which I am indebted to Mr. Salter, there was a gradual change from the floral to the foliar condition; thus there were five distinct lanceolate sepals, the arrangement of whose veins betokened that they were leaf-sheaths rather than perfect leaves, ten petals partly foliaceous and sheath-like as to their venation, one of them funnel-shaped, but whether from dilatation or cohesion of the margins could not be determined. The stamens were eight or ten in number, their connectives prolonged into foliaceous or petaloid appendages, so that the filament represented the stalk of the leaf. The pistil was entirely absent and its place was supplied by a branch with numerous perfectly formed stipulate leaves.

Some flowers of Anagallis arvensis described by Dr. Marchand[119] are so interesting and show so well the gradual stages by which this malformation is arrived at, that it is desirable to cite the summary of Dr. Marchand's researches as given in the 'Gardeners' Chronicle' by Mr. Berkeley, taking that instance first in which the parts of the flower departed least from the normal condition, and then the others in their proper order. In all the parts there was a greater or less tendency to assume a green tint; in some they were entirely green, in others the brighter colours were confined to the more recently developed parts.

"1. In the first case then, the sepals and petals were in their normal position, though rather more dilated than usual; the anthers were fertile, the principal change existing in the ovary, the upper part of which was wanting, so that the ovules were exposed seated on the central placenta.

2. In the next step the calyx, more developed than usual, was separated from the corolla by a long peduncle, and the ovary, which was ovate, contained instead of a placenta a sort of plumule or young shoot.

3. In this case the corolla and calyx were distant from each other; there was no trace of stamens, but the axis was continued from the centre of the corolla, and ended in a leaf-bud.

4. The calyx and corolla nearly as before, but instead of stamens a whorl of little leaves was developed, in the centre of which the axis was continued, bearing at its tip two whorls of leaflets, alternately three and three.

5. In this case two out of the five stamens were normal, the other three changed into leaves, showing clearly the origin of the leaflets, in the last case, which took the place of the stamens.

6. The ovary varied in different flowers. In some the placenta was crowned with ovules; in others the ovules were replaced by a single whorl of leaflets; in others there was every shade of change from ordinary ovules to perfect leaflets; while in others, again, every ovule was converted into a leaf with a long petiole.

7. In these flowers shoots were developed in the axils of the sepals, or on the face of the petals between the point of their insertion and that of the stamens, and, what is most curious, in the interior of the ovaries round the foot of the placenta.

8. Here, again, a very singular condition presented itself: the calyx and corolla separated from each other, the stamens partly developed, the axis continued beyond the corolla, branched and bearing normal leaves so as exactly to resemble an ordinary stem, while in consequence of the calyx and corolla being bent down to the ground, adventitious roots were developed from the axis on the under side above each of them. In another case, where the calyx and corolla were approximated, the ovary was open above, and sent out six shoots from within, perfectly developed, clearly representing the central placenta and five axile buds, and each giving out a number of adventitious roots at its base."

In other genera of the same order (Primulaceae) an extension of the placenta into a leafy branch has been observed, as in Lysimachia, where in one case the prolonged placenta was removed and struck as a cutting.[120]

In Ericaceae too, the axile placenta has been seen ovuliferous at the base and prolonged above into a leafy branch.[121]

Median floral prolification.—This is of more frequent occurrence than the preceding. The prolonged axis is more frequently terminated by a flower-bud than by a leaf-bud, though it must be remarked, that the lengthened and protruded stem frequently bears leaves upon its sides, even if it terminate in a flower, and thus the new growth partakes of a mixed leafy and floral nature. Instances of this kind have long been familiar to observers, and have always excited attention from the singularity of their appearance. In one of the old stained-glass windows, apparently of Dutch manufacture, in the Bodleian Picture Gallery at Oxford, is a representation of a Ranunculus affected with median floral prolification.[122] In pinks the affection is not unfrequently met with. Fig. 60 shows an instance of the kind copied from Schotterbec.

A singular instance of prolification in the central flower of one of the verticillasters of Phlomis fruticosa fell under my own notice; it was a case wherein the calyx was torn on one side, and one of its lobes had become petaloid. Between the calyx and the corolla were three or four spathulate, hairy, bract-like organs; the corolla and stamens were unchanged; but in place of the usual four-lobed ovary there was a single carpel with a basilar style, terminated by a forked stigma. Occupying the place of the other lobes of the pistil was an oblong woolly flower-bud, consisting of calyx, corolla, and stamens, but with no trace of pistil. I have been unable to find recorded any instance of malformation among Labiates or Borages at all similar to this. It differed from most other examples of prolification in that the axis was not prolonged, the adventitious bud occupying precisely the position of the three lobes of the ovary that were absent. The sole remaining carpel had a style and a stigma as perfect in appearance as though the pistil had been complete.



In a flower of Conostephium (Epacridaceae) forwarded to me by Mr. Bentham, there was a similar adventitious bud placed by the side of the pistil, but as the latter contained the usual number of cells it is probable that the supernumerary bud in this case originated rather from the side than the end of the axis.

Certain families of plants present this deviation from their ordinary structure with greater frequency than others: the following orders seem to be the most frequently affected by it: Ranunculaceae, Caryophyllaceae, Rosaceae; while it is commonly met with in Scrophulariaceae, Primulaceae and Umbelliferae. Of genera which seem peculiarly liable to it may be mentioned the following: Anemone, Ranunculus, Cheiranthus, Dianthus, Dictamnus, Daucus, Rosa, Geum, Pyrus, Trifolium, Antirrhinum, Digitalis, Primula.

A reference to the subjoined list of genera affected by this malformation, and the knowledge of its comparatively greater frequency in some than in others of them, will show that it is more often met with in plants having an indefinite form of inflorescence than in those having a definite one. The change may affect some only, or the whole of the flowers constituting an inflorescence; and though it is by no means a constant occurrence, it very frequently happens that the central or terminal flower in a definite inflorescence is alone affected, the others remaining in their ordinary condition, as in pinks (Dianthus); and in the indefinite forms of inflorescence, it is equally common that the uppermost flower or flowers are the most liable to be thus affected.

In those plants which present this deviation from the ordinary condition with the greatest frequency, it often happens that the axis is normally more or less prolonged, either between the various whorls of the flower, as in the case of the gynophore, &c., or into the cavity of the carpels, as in the instances of free central placentation. To bear out this assertion, the following instances taken from those genera having definite inflorescence, and which are very commonly affected with prolification, may be cited; thus, in Anemone and Ranunculus the thalamus is prolonged to bear the numerous carpels; in Dianthus there is a marked internode separating the carpels from the other parts of the flower; in Primulaceae central prolification is very common, and this is one of the orders where the placenta seems from the researches of Duchartre and others, to be truly a production of the axis within the carpels;[123] in Thesium also, another genus with free central placenta, this malformation has been found.

So also among plants with indefinite inflorescence, prolification seems very frequently to affect those wherein the axis is normally prolonged; thus it is common in Dictamnus, which plant has an internode supporting the pistil; it is frequent among Umbelliferae, where the carpophore may be truly considered an axile production; it is common among Rosaceae and Ranunculaceae, in many of which the axis or thalamus is well-marked, and it is by no means infrequent in the flowers of the Orange, where the floral internodes are also slightly elongated; on the other hand, there is no case on record in Magnoliaceae, and some other orders where the floral part of the axis is at some point or other elongated; still, on the whole, there can be but little doubt that there is a real relation between prolification and the normal extension of the floral internodes.

Under these circumstances, those instances wherein the parts of the flower become separated one from the other by the elongation of the internodes (apostatis), constitute a lesser degree of the same change, which operates most completely in the formation of a new bud at the extremity of the prolonged axis. Some specimens of Geum rivale (a plant very liable to become prolified) in my possession show this very clearly. In the wild plant the thalamus is elevated on a short stalk; in the abnormal ones the thalamus is simply upon a longer stalk than usual, or in a more advanced stage of the deviation the lengthened thalamus takes the form of a branch provided with leaves and terminated by a flower; it is noticeable, also, in these specimens, that the sepals of the lower flower have assumed entirely the dimensions and appearance of leaves.

Median prolification has occasionally been recorded in flowers that have, in their ordinary condition, but one carpel, as in Leguminosae and in Santalaceae. In Leguminosae, as also in Amygdalus, it would seem as if the adventitious bud were strictly a lateral and axillary production, and moreover that the carpel itself is not strictly terminal but lateral in position, though apparently terminal from the abortion of other carpels. In the only recorded instance that I am aware of, of this malformation affecting the genus Thesium, the pistil was altogether absent, and occupying its place was the new bud or branch.[124]



As the carpels are not unfrequently absent in cases of median prolification, it has been thought that the pistil in such cases was metamorphosed into a stem bearing leaves or flowers. Setting aside the physiological difficulties in the way of accepting such an opinion, an examination of any number of cases is sufficient to refute it; for, as Moquin well remarks, the carpels may frequently be found either in an unaltered condition or more or less modified.

If the pistil be normally syncarpous, its constituent carpels, if present at all in the prolified flower, become disjoined one from the other to allow of the passage between them of the prolonged axis; thus in some malformed flowers of Daucus Carota gathered in Switzerland (fig. 61), not only was the calyx partially detached from the pistil, but the carpels themselves were leaf-like, disjoined, and unprovided with ovules; between them rose a central prolongation of the axis, which almost immediately divided into two branches, each terminated by a small umbel of perfect flowers, surrounded by minute bracts.[125]

Not only are the carpels thus frequently separated one from the other by the prolonged axis, but they undergo commonly a still further change in becoming more or less completely foliaceous, as in the Daucus just mentioned, where the carpels were prolonged into two lance-shaped leaves, whose margins in some cases were slightly incurved at the apex, forcibly calling to mind the long "beaks" that some Umbelliferous genera have terminating their fruits—for instance, Scandix. Dr. Norman, in the fourth series of the 'Annales des Sciences,' vol. ix, has described a prolification of the flower of Anchusa ochroleuca, in which the pistil consisted of two leaves, situated antero-posteriorly on a long internode, with a small terminal flower-bud between them; and numerous similar instances might be cited.

In this place may also be noticed those instances wherein the placenta elongates so much that the pericarp becomes ruptured to allow of the protrusion of the placenta, although this prolongation is not attended by the formation of new buds. Cases of this kind occurring in Melastoma and Solanum have been put on record by M. Alph. de Candolle.[126] This is a change analogous with that which occurs in some species of Leontice or Caulophyllum, as commented on by Robert Brown. See 'Miscellaneous Botanical Works' of this author, Ray Society, vol. i, p. 359.

If the pistil be apocarpous, and the carpels arranged spirally on an elevated thalamus, it then frequently happens that the carpels, especially the upper ones, become carried up with the prolonged axis, more widely separated one from the other than below, and particularly liable to undergo various petalloid or foliaceous changes as in proliferous Roses, Potentilla, &c.



Fig. 62, copied from Cramer, shows an instance of this kind in Delphinium elatum, where not only is the thalamus prolonged, and the carpels separated, but from the axils of some of the latter which have assumed from the disunion of their margins somewhat of the appearance of leaves, other flowering branches proceed—axillary prolification. If, on the other hand, the carpels be few in number, and placed in a verticillate manner, the axis then generally passes upwards without any change in the form or position of the carpels being apparent, as in a proliferous columbine, figured in the 'Linnean Transactions,' vol. xxiii, tab. 34, fig. 5.

When a flower with the ovary naturally inferior or adherent to the calyx becomes prolified, a change in the relative position of the calyx and ovary almost necessarily takes place, the latter becoming superior or detached from the calyx; this has been already alluded to in Umbelliferae. In a species of Campanula examined by me, the calyx was free, the corolla double, the stamens with petaloid filaments, and in the place of the pistil there was a bud consisting of several series of green bracts, arranged in threes, and enclosing quite in the centre three carpellary leaves detached from one another and the other parts of the flower, and open along their margins, where the ovules were placed. In other similar instances in the same species of Campanula, the styles were present, forming below an imperfect tube which surrounded the adventitious bud; in another, contrary to what occurs usually in such cases, the ovary was present in its usual position, but surmounted by a bud of leafy scales, enclosed within the base of a tube formed by the union of the styles. A similar relative change in the position of the calyx and the ovary takes place when the Compositae are affected with central prolification, or even in that lesser degree of change which merely consists in the separation and disunion of the parts of the flower, but which in these flowers appear to be, as it were, the first stage towards prolification. I owe to the kindness of Professor Oliver a sketch of a species of Rudbeckia? showing this detachment of the calyx from the ovary. In a monstrous Fuchsia that I have had the opportunity of recently examining, the calyx was similarly detached from the ovary simultaneously with the extension of the axis. Here the petals were increased in number and variously modified, the stamens also; while in the centre and at the top of the flower, conjoined at the base with some imperfect stamens, was a carpel open along its ovuliferous margins. Such instances as these seem to be the first stages of a change which, carried out more perfectly, would result in the formation of a new bud on the extremity of the prolonged axis.

In Orchidaceae, among which family I have now met with several instances of prolification, the ovary seems usually to be absent. Fig. 63 shows a prolified flower of Orchis pyramidalis in which the perianth was nearly regular, the central portions of the flower absent, and their place supplied by a new miniature raceme. This specimen was forwarded to me by Dr. Moore, of Glasnevin.



As might be expected, it very rarely happens that median prolification occurs without some other deviation in one or more parts of the flower being simultaneously manifested. Some of these changes have been already mentioned, but others are commonly met with, as, for instance, the multiplication or doubling, as it is termed, of the petals; others, though less frequent, are of more interest. Fusion of two or more flowers in association with prolification is especially common in cultivated specimens of Digitalis purpurea; the uppermost flowers of the raceme become fused together so as to form one large, regular, erect, cup-shaped corolla, to the tube of which the stamens are attached, in greater number than ordinary, and all of equal length; the bracts and sepals are confusedly arranged on the exterior of the flower; while in the centre, in the place usually occupied by the pistil, there rises a conical prolongation of the axis, bearing at its outer or lower portion a number of open carpels, provided, it may be, with styles and ovules; these enclose an inner series of scale-like bracts, from whose axils proceed more or less perfect florets; so that in the most highly developed stage a perfect raceme of flowers may be seen to spring from the centre of a cup-shaped regular flower, whose lobes show its compound character. All intermediate stages of this malformation may be found from cases where there is a simple fusion of two flowers with a second verticil of carpels within the outer, up to such cases as those which have been just mentioned. It is worthy of special remark, that in all these cases the flowers at the uppermost part of the raceme are alone affected, and that, in addition to the prolification, there is fusion of two or more flowers, and regularity in the form of the compound corolla and stamens.

The calyx of a prolified flower is either unchanged, or it is modified in harmony with the changes in the central part of the flower. If the ovary be normally superior or free from the calyx, then the latter is comparatively rarely altered; for instance, in proliferous pinks (Dianthus) the calyx is seldom affected, except, indeed, in those instances where the floral axis is prolonged, and produces from its side a successive series of sepals, as in what is called the wheat-ear carnation; but though these instances may be, as I believe, an imperfect degree of prolification, they do not affect the general truth of the above opinion, that the calyx, if it be free from the ovary, is but rarely changed in a prolified flower; but that this is not a universal rule is shown by proliferous flowers of Geum rivale, where the sepals are usually large and leaf-like, as they likewise are frequently in proliferous roses and pears.



Proliferous roses have a special interest, inasmuch as they show very conclusively that the so-called calyx-tube of these plants is merely a concave and inverted thalamus, which, in prolified specimens, becomes elongated (fig. 64) after the fashion of Geum rivale, &c.[127] Occasionally from the middle of the outer surface of the urn-shaped thalamus proceeds a perfect leaf, which could hardly be produced from the united sepals or calyx-tube; a similar occurrence in a pear is figured in Keith's 'Physiological Botany,' plate ix, fig. 12.

The change which the calyx undergoes when flowers with an habitually adherent ovary become prolified, and wherein the calyx is disjoined from the ovary, has been before mentioned, but it may also be stated that, under such circumstances, the constituent sepals are frequently separated one from the other, and not rarely assume more or less of the appearance of leaves, as in proliferous flowers of Umbelliferae, Campanulaceae, Compositae, &c.

As to the corolla, it was long since noticed that prolification was especially liable to occur in double flowers; indeed, Dr. Hill, who published a treatise on this subject, setting forth the method of artificially producing prolified flowers, deemed the doubling to be an almost necessary precursor of prolification;[128] but, though frequently so, it is not invariably the case that the flower so affected is double—e.g. Geum. If double, the doubling may arise from actual multiplication of the petals, or from the substitution of petals for stamens and pistils, according to the particular plant affected. Occasionally in prolified flowers the parts of the corolla, like those of the calyx, become foliaceous, and in the case of proliferous pears fleshy and succulent. There is in cultivation a kind of Cheiranthus? in which there is a constant repetition of the calyx and corolla, conjoined with an entire absence of the stamens and pistils; a short internode separates each flower from the one above it, and thus frequently ten or a dozen of these imperfect flowers may be seen on the end of a flower-stalk, giving an appearance as if they were strung like beads, at regular intervals, on a common stalk. I have seen a similar instance in a less degree in a species of Helianthemum.

The stamens are subject to various changes in prolified flowers; they assume, for instance, a leaf-like or petal-like condition, or take on them more or less of a carpellary form, or they may be entirely absent; but none of these changes seem to be at all necessarily connected with the proliferous state of the flower. Of more interest is the alteration in the position of these organs which sometimes necessarily accrues from the elongation of the axis and the disjunction of the calyx; thus, in proliferous roses the stamens become strictly hypogynous, instead of remaining perigynous. In Umbelliferae the epigynous condition is changed for the perigynous, &c.

The condition of the pistillary organs in prolified flowers has already been alluded to. Hitherto those instances have been considered in which either the carpels were absent, or the new bud proceeded from between the carpels. There is also an interesting class of cases where the prolification is strictly intra-carpellary; the axis is so slightly prolonged that it does not protrude beyond the carpels, does not separate them in any way, but is wholly enclosed within their cavity. Doubtless, in many cases, this is merely a less perfect development of that change in which the axis protrudes beyond the carpels. This intra-carpellary prolification occurs most frequently in plants having a free central placenta, though it is not confined to them, as it is recorded among Boragineae. A remarkable instance of this is described by Mr. H. C. Watson in the first volume of Henfrey's 'Botanical Gazette,' p. 88. In this specimen a raceme of small flowers was included within the enlarged pericarp of a species of Anchusa. But the most curious instances of this form of prolification are, no doubt, those which are met with among Primulaceae and other orders with free central placentation.

Duchartre, in his memoir on the organogeny of plants with a free central placenta, in the 'Ann. des Sc. Nat.,' 3 ser., 1844, p. 290, among other similar instances, mentions two flowers of Cortusa Matthioli, wherein the placenta was ovuliferous at the base; but the upper portion, instead of simply elongating itself into a sterile cone, had produced a little flower with its parts slightly different from those of the normal flowers. M. Alph. de Candolle has likewise described somewhat similar deviations, and one in particular in Primula Auricula, where the elongated placenta gave off long and dilated funiculi bearing ovules, while other funiculi were destitute of these bodies, but were much dilated and foliaceous in appearance.[129] In some flowers of Rhododendron I have observed a similar condition of the ovules, which, moreover, in the primary flowers, were attached to the walls of the carpels—parietal placentation.

In speaking of these as cases of intra-carpellary prolification, it is, of course, impossible to overlook the fact that they differ in degree only from those cases where the lengthened axis projects beyond the cavity of the carpels; nevertheless they seem to demand special notice, because in these particular plants the placenta or its prolongation appears never to protrude beyond the carpels, or at least very rarely. There are, however, numerous instances of such an extension of the placenta and of prolification occurring among Primulaceae in conjunction with the more or less complete arrest of growth of the carpels.[130] An instance of this kind has come under my own notice in a monstrosity of the chinese primrose, in which the carpels were reduced to a hardly discernible rim surrounding an umbel of five rays, each terminated by a small normally constituted flower-bud.

The ovules of a prolified flower are either unaffected, or they occur in a rudimentary form, or, lastly, they may be present in the guise of small leaves.

Under the term prolification of the fruit two or three distinct kinds of malformation appear to have been included. The term seems usually to be applied to those cases where from the centre of one fruit a branch bearing leaves, flowers, or another fruit, is seen to project, as happens occasionally in pears. Now, in many instances, not only the fruit, is repeated, but also the outer portions of the flower, which wither and fall away as the adventitious fruit ripens; so that at length the phenomenon of one fruit projecting from another is produced. It is obvious that this form of prolification in no wise differs from ordinary central prolification. Sometimes some of the whorls of the adventitious flower are suppressed; thus, M. Duchartre describes some orange blossoms as presenting alternating series of stamens and pistils one above another, while the calyces and corollas belonging to each series of stamens and pistils were entirely suppressed.[131] In other cases, doubtless, the carpellary whorl is alone repeated, the other whorls of the adventitious flower being completely absent.

Another condition, apparently sometimes mistaken for prolification of the fruit, is that in which the carpellary whorl becomes multiplied; so that there is a second or even a third series within the outer whorl of carpels. If the axis be at all prolonged, then these whorls are separated one from the other, and produce in this way an appearance of prolification. This happens frequently in oranges, as in the variety called Mellarose.[132]

Moquin has given an explanation of the St. Valery Apples, wherein the petals are sepaloid, the stamens absent, and where there is a double row of carpels, by supposing these peculiarities to be due to "a prolification combined with penetration and fusion of two or more flowers," but it is surely more reasonable to conceive a second row of carpels placed above the first by the prolongation of the central part of the axis. Supposing this view to be correct, the inner calyx-like whorl might be considered either as a repetition of the calycine whorl, or it might be inferred that the corolla was present in the guise of a second calyx.

Moquin-Tandon suggests another explanation—namely, that though the stamens are absent in these curious flowers, at least in their ordinary shape, they are represented by the lower row of carpels, which become, in process of development, fused with the upper or true carpels. If this were so, surely some intermediate conditions between stamen and carpel would occasionally be present; but such does not appear to be the case.[133]

In some of the instances of so-called proliferous pears the carpels would seem to be entirely absent, and the dilated portion of the axis to be alone repeated. Thus, the axis dilates to form the lower fruit without any true carpels being produced, but at its summit a whorl of leaves (sepals) is formed; above these another swelling of the axis takes place also without the formation of carpels, and this, it may be, is terminated in its turn by a branch producing leaves. In these cases there is no true prolification, but simply an extension of the axis. That the outer portion (so-called calyx-tube) of these fruits is really an axile product there can now be little doubt; and, as if to show their axile nature, they occasionally produce leaves from their sides, as before mentioned. Moquin, in the tenth volume of the 'Bulletin of the Botanical Society of France,' p. 73, says that when the case is one of prolification the lower fruit is larger and is formed of a fleshy mass; moreover, the line of demarcation between the fruits is more distinct, and there are traces of the seed-bearing cavity in the interior, and of calycine lobes at the top. On the other hand, if the case be one of hypertrophy merely, the lowermost fruit is the smallest, and there is no trace of seed-bearing cavity nor of sepals. See also under Hypertrophy.

Some other malformations usually referred to prolification of the fruit seem due to branching of the inflorescence, as in Plantago, wheat, maize; or to a simple extension of the axis beyond its ordinary limit, as in some cones of firs, &c. It is obvious that the true fruits in these cases are in no wise affected.

From these considerations it would appear better to abandon the use of the expression prolification of the fruit, as unnecessary where it is really applicable, and as delusive in the numerous other cases where it is employed.

Median prolification of one or other kind has been met with in the following genera:

Leafy. Floral.

Ranunculaceae. Clematis. Anemone! *Anemone! Ranunculus! *Ranunculus! Delphinium. Caltha. Aquilegia! Cruciferae. Bunias. *Cheiranthus! Erucago. *Matthiola! Sisymbrium! Brassica! Nasturtium. Hesperis. Sinapis! Diplotaxis. Lunaria. Erysimum. Alyssum. Peltaria. Cardamine! Cleome. Cistaceae. Helianthemum! Caryophylleae. Dianthus! *Dianthus! Silene! Lychnis! Violaceae. Viola! Tiliaceae. Triumfetta! Geraniaceae. Geranium! Sapindaceae. Pavia! Pavia! Malvaceae. Paritium. Hibiscus! Malpighiaceae. Byrsonima! Rutaceae. Genera not specified. *Dictamnus! Resedaceae. Reseda. Caylussa! Aurantiaceae. *Citrus! Vitaceae. Vitis. Vitis. Umbelliferae. Heracleum. Angelica. Thysselinum. *Athamanta. *Daucus! *Torilis. Rosaceae. *Rosa! *Rosa! *Geum! *Geum! Agrimonia. Amygdalus. Prunus! Spiraea! Spiraea! Rubus. *Pyrus! *Pyrus! ?Leguminosae Trifolium! Medicago! Melilotus. Pisum! Cucurbitaceae. Cucumis. Passifloraceae. Passiflora. Philadelphaceae. Philadelphus. Onagraceae. Epilobium! Epacridaceae. Epacris! Ericaceae. *Erica. Rhododendron! Convolvulaceae. Convolvulus. Gentianaceae. Gentiana. Gentiana. Apocynaceae. Vinca. Jasminaceae. Jasminum! Scrophulariaceae. Verbascum! Antirrhinum! *Digitalis! *Linaria! Veronica. Orobanchaceae. Orobanche. Labiatae. Genera not specified. Stachys. Phlomis! Hydrophyllaceae. Hydrophyllum. Boraginaceae. Anchusa. Symphytum. Primulaceae. *Dodecatheon. *Cortusa. *Anagallis! *Anagallis! *Primula. Dipsacaceae. Scabiosa. Compositae. Hieracium! Hieracium! Cirsium. Cirsium. Hypochaeris. Calendula! Spilanthes. Carthamus. Coreopsis. Campanulaceae. Campanula. *Campanula! Polygonaceae. Genera not specified. Rumex. Santalaceae. Thesium. Liliaceae. Genera not specified. Tulipa! Hemerocallis! Asphodelus. Hyacinthus! Iridaceae. Iris. Amaryllidaceae. Narcissus! Leucojum. Orchidaceae. Orchis! Habenaria. Cyperaceae. Carex. Gramineae. Phleum.

Axillary prolification is the term applied to those cases wherein one or more adventitious buds spring from the axils of one or more of the parts of the flower. Engelmann makes use of the word ecblastesis to denote the same condition. Both terms are open to the objection that they do not clearly enable us to distinguish prolification occurring within the flower from a similar state originating outside the flower, within the bracts of the inflorescence. This latter condition, called by Moquin-Tandon lateral prolification (see Prolification of the Inflorescence), is as truly axillary as that to which the name is restricted. In consequence of certain peculiarities in the structure of some flowers, to be hereafter alluded to, it is not in all cases easy to decide whether the new growth springs from the interior of the flower, or from the inflorescence beneath the flower.

The accessory bud presents itself as a leaf-bud, a branch, a flower-bud, or a miniature inflorescence; it may be sessile, but is far more frequently stalked, and in more than half the number of cases it is a flower-bud or an inflorescence. There may be one or more of these buds; if two only, then they are usually placed directly opposite one to the other, on the opposite sides of the flower.

It will be seen, from the appended list, that the orders and genera in which this description of adventitious growth occurs most frequently are the following:—Cruciferae, especially the genus Brassica; Caryophyllaceae, e.g. Dianthus; Resedaceae; Leguminosae, e.g. Melilotus, Trifolium, &c.; Rosaceae, e.g. Rosa, Potentilla, &c.; Umbelliferae, and Campanulaceae. For the most part, these are groups also peculiarly liable to central prolification.

All the parts of the flower may be thus affected; but, as might have been anticipated from the foliaceous nature of the sepals, the new bud usually arises from within the axil of one of those organs. Next in frequency to the calyx, the pistil is subjected to this change—the carpels in such a case being disunited and leaf-like. The petals rank next, and lastly the stamens; these latter, indeed, are usually, but not invariably, absent, the new growth occupying their position. Hence it may well be that when such is the case, there is no real axillary prolification, but rather the substitution of a bud for a stamen. Generally, however, the position of the accessory bud is such that it may properly be referred to the axil of an undeveloped or rudimentary stamen.

The largest number of instances of this malformation, not merely generically, but also individually, occurs in plants the members of whose floral whorls are not united one to the other; thus, it is far more common in polypetalous plants than in gamopetalous ones. In the prolified flowers belonging to the latter group, the sepals, if not actually uncombined, are only united for a short distance. The same relationship, but in a much less degree, exists in the case of median prolification, as that aberration is likewise most commonly met with in polypetalous flowers. Another feature of interest is the rarity with which axillary prolification is found in irregular gamopetalous blooms. It may be that the irregular and comparatively excessive growth in some parts of these flowers, as compared with others, may operate in checking any luxuriant tendency in other directions.

As in the case of median prolification, plants having an indefinite inflorescence are more liable to be affected with ecblastesis than those having a definite one. The degree of branching of the inflorescence may be noticed, as this deformity is far more common in plants whose peduncles are branched than in those which have either a solitary flower or an unbranched flower-stalk. More than two thirds of the entire number of genera cited as the subjects of this malformation have a branched inflorescence of some form or other; and about two thirds of the cases occur in genera having some form of indefinite inflorescence. If individual instances could be accurately computed, the proportion would be even higher.

Fully three fourths of the entire number of genera recorded as occasionally the subjects of this irregularity possess in their usual state some peculiarity of the thalamus; for instance, in about a third of the whole number of genera the thalamus is more or less prolonged between some or other of the floral whorl, e.g. Caryophyllaceae, Potentilla, Anemone, Dictamnus, Umbelliferae, &c. About one fourth of the genera have numerous stamens or numerous carpels, or both, springing naturally from the thalamus. In others (about one sixth) the thalamus is enlarged into a disc, or else presents one or more glandular swellings, e.g. Reseda, Nymphaea, Cruciferae. In the last-named family, as has been already remarked, prolification is very common. It would be interesting to ascertain precisely what part of an inflorescence is most liable to this affection; but as information on this point is but rarely given in the records of these cases, I can only give the results of my own observations, which go to show that, in a many-flowered inflorescence, those flowers at the outside, or at the lower portion, seem to be more frequently the subjects of this change than those situated elsewhere. This may probably be accounted for by the fact that the malformation is met with most generally in plants with an indefinite form of inflorescence, and therefore the lowermost or outermost flowers are most fully nourished; the upper flowers being in a less advanced condition, the change is more likely to be overlooked in them; or it may be that from the unusual luxuriance in the lower flowers, the upper ones may be either present in their ordinary condition, or may be (as indeed frequently happens) stunted in the size and proportion of their several parts.

Axillary foliar prolification of the flower.—The formation of an adventitious leaf-bud in the axil of any of the parts of the flower is not of such common occurrence as the development of a flower-bud in similar situations, nor is it so frequent as median foliar prolification. I have seen leafy shoots proceeding from the axils of the sepals in the flowers of Brassica, and a similar occurrence has been noticed in Caltha palustris, Herreria parviflora, and other plants. Dr. Marchand's flowers of Anagallis, previously referred to at p. 117, showed good illustrations of this occurrence, as also some specimens described by Kirschleger in A. phoenicea.[134] Steinheil has figured and described[135] a flower of Scabiosa in which there was an adventitious formation of leafy shoots in the axil of the outer calyx. In some flowers, such as Convolvulus, Anemone, &c., the exact nature of the sub-floral leaves is uncertain, i.e. it is open to doubt whether the organs in question are bracts or leaves pertaining to the inflorescence, or whether they are really parts of the flower. When leafy shoots are formed in the axils of such organs, the adventitious growth may be referred to extra-floral prolification, prolification of the inflorescence that is, or to axillary prolification, according to the view taken of the real nature of the sub-floral leaves. So far as the mere occurrence of prolification is concerned, it is not very material which view be adopted. The same remark applies to cases where leaf-buds occur on the outer surface of inferior ovaries, as in Rosaceae, Pomaceae, Philadelphus, or Tetragonia expansa, as elsewhere mentioned.

It would seem more consistent with the general arrangements of parts, that the adventitious buds should be formed more frequently outside than within the flower proper.

Knight[136] figures and describes the occurrence of small tubers or fleshy leaf-buds in the axils of the sepals of a potato, a curious illustration of the real morphological nature of the tuber.

Axillary floral prolification of the flower.—As already stated, this is of more common occurrence than the formation of a leaf-bud in a similar situation. Any of the parts of the flower may thus subtend a flower-bud, though probably the new buds more frequently originate in the axils of the sepals than in the other whorls. In Cruciferae the change in question is, relatively speaking, very common. In cauliflowers and broccoli I have frequently met with stalked flowers proceeding from the axils of the sepals, so also in some fuchsias I have seen a ring of stalked flower-buds alternating with the petals, which, together with the stamens and pistil, remained unaffected. The number of parts in the supernumerary structures is generally less than the normal flowers.

In Mr. Herbert Spencer's 'Principles of Biology,' part iv, p. 37, are figured and described some monstrous inflorescences in Angelica and other Umbelliferae, from which, amongst other things, the author draws the conclusion that there is no absolute distinction between leaf and branch. Without staying for the moment to discuss this matter, it may here be said that the Umbellifers in question apparently owe their peculiarities rather to axillary prolification within the flower, or to prolification of the inflorescence, than to an actual transformation of a flower or any portion of a flower into an umbellule.[137]

In the 'Gardeners' Chronicle,' 1855, p. 551, an instance is figured of the production of a supernumerary flower proceeding from the axil of a stamen in a species of Nymphaea (fig. 65). The ovary in this case was wanting, but in its place was a tuft of small leaves. It is curious that among Dr. Kirk's drawings of east tropical African plants now at Kew, there should be one representing a precisely similar state of things. The species in both instances was Nymphaea Lotus, or a cultivated variety of it.

M. Wesmael[138] describes a very singular case of what appears to have been referable to axillary prolification in the flowers of Carex acuta. The rachillus is described as prolonged through the utricle by the side of the stigmas, bearing on its side a bract, then a secondary utricle, from the axil of which sprung a short stem surmounted by an ovary. Wigand, 'Flora,' 1856, mentions a similar change in Carex glauca. In this instance the base of the female inflorescence bore lateral spikes, which projected from the utricles; some of these adventitious spikes were female, others female below and male above, others, again, wholly male.



Various changes in the form and arrangement of the several floral whorls accompany axillary prolification; some of these affect the particular organ or organs implicated, and these only, while in other cases some other parts of the flower likewise undergo modification. The changes most commonly met with are such as may be classed under Goethe's theory of retrograde metamorphosis; for instance, if a supplementary bud be developed in the axil of a sepal, that sepal is likely to be more than ordinarily leaf-like in appearance. The dislocation of the affected sepal from its fellows is a very frequent occurrence; in cases of this kind the detached sepal is placed below the others, thus approximating, in position as well as in function, to the bracts. In some of the instances of proliferous pears, on which I shall have occasion to comment, the sepals are described as sharing in the succulent character of the fruit.

The petals, under such circumstances, often exist in the guise of sepals or of small leaves; and instances are recorded wherein the place of the calyx and corolla was supplied by a succession of overlapping green scales, from the axils of which the new buds arose. M. Germain de Saint Pierre records such a case in Trifolium repens, wherein the calyx and corolla were replaced by overlapping scales, in the axils of each one of which arose a flower; above there was a row of stamens, and in the centre a pistil in the guise of a trifoliate leaf.[139] Such instances seem to afford an extreme degree of a more common change, viz., the diminished size and contracted appearance of the sepals and petals when affected with axillary prolification. They have also a close relationship to such developments as we see in the wheat-ear carnation, in certain species of the genus Maesa and others, wherein the calyx is repeated over and again, to the partial or complete suppression of the other parts of the flower. All these cases may be in part explained by the operation of the principle of compensation.

So far as the androecium is concerned, the stamens either remain unaltered, or they are present in a more or less petal-like condition; but it far more frequently happens that the stamens are entirely suppressed, the adventitious bud supplying their place; thus was it in the Dianthus represented in the adjoining woodcut, fig. 66, where the stamens were entirely absent, and their places supplied by flower-bearing branches. This Dianthus has the more interest from its similarity to the one described by Goethe, Metam. der Pflanzen, cap. 16, sect. 105; but in that instance median prolification also existed. For my specimens I am indebted to Mr. T. Moore.



The pistil, too, is necessarily subject to very grave alterations when affected with this malformation. It is separated into its constituent carpels; and these assume a leaf-like aspect, and are in the great majority of instances destitute of ovules. Indeed, virescence or chloranthy is very intimately connected with this aberration, as might have been anticipated, for if the parts of the flower assume more or less of the condition of stem-leaves or bracts, it is quite natural to expect that they will partake likewise of the attributes of leaves, even at the expense of their own peculiar functions.

It occasionally happens that an adventitious bud arises from the axil of a monocarpellary pistil. This takes place sometimes in Leguminosae, and seems to have been more frequently met with in Trifolium repens than in other plants. The species named is, as is well known, particularly subject to a reversion of the outer whorls of the flower to leaves, and even to a leaf-like condition of the pistil. There are on record instances wherein a leaf-bud has been placed in the axil of a more or less leaf-like carpel; while at other times a second imperfect carpel has been met with in the axil of the first.[140] I have myself seen numerous imperfectly developed cases of this kind.

It may be asked whether such cases are not more properly referable to central prolification—whether the axis is not in such flowers terminated by two, rather than by one carpel? It is, however, generally admitted by morphologists that the solitary carpel of Leguminosae is not terminal, but is the sole existing member of a whorl of carpels, all the other members of which are suppressed as a general rule, though exceptional instances of the presence of two and even of five carpels have been described.[141]

Again, the adventitious bud or carpel is placed, not laterally to the primary one, or opposite to it, on the same level, but slightly higher up—in fact, in the axil of the primary carpellary leaf. Griffith figures and describes[142] an instance of the kind in a species of Melilotus. The stalk of the ovary is mentioned as having a sheathing base, bearing in its axil a prolongation of the axis of inflorescence, in the form of a short spike with hairy bracts and imperfect flowers, the latter having a well-formed calyx and rudimentary petals and stamens. Griffith infers, from this specimen, that the legume is not to be considered as a terminal leaf.

List of Genera in which Axillary Prolification has been observed.

Order Genus. Leaf-bud Flower-bud or From what organ. or Branch Inflorescence

Ranunculaceae Clematis Flower-bud Sepals. Caltha Ditto Ditto. Aconitum Ditto. Delphinium Ditto Sepals, carpels, &c. Anemone! Ditto Involucre? Nymphaeaceae Nymphaea! Fruit? Nymphaea Flower Petal. Cruciferae *Brassica! Leaf-bud Flower-bud Sepals and petals. Brassica! Ditto Stamens. Brassica! Ditto Ditto Pistil. Cardamine! Ditto Sepals. Matthiola! Ditto Sepals and petals. Cheiranthus! Ditto Sepals. Erysimum Ditto Sepals and pistils. Lepidium! Ditto Petals and stamens. Arabis Ditto Sepals. Diplotaxis Flower, Pistil, calyx inflorescence and corolla. Capsella Capparidaceae Cleome Flower-bud Sepals. Resedaceae *Reseda Ditto Ditto. Caryophyllaceae Arenaria Branch Ditto. Agrostemma Leaf-bud Ditto. *Lychnis Ditto Stellaria Ditto Silene Ditto *Gypsophila Ditto Ditto Sepals and stamens. *Dianthus! Ditto Ditto Sepals. Dianthus! Ditto Inflorescence Petals and stamens. Cucubalus Sepals Saponaria! Sepals and petals. Malvaceae Alcea Flower-bud Stamen. Aurantiaceae Citrus! Ditto Ditto. Rutaceae Dictamnus! Ditto Pistil leafy. Tropaeolaceae Tropaeolum! Ditto Petals. Celastraceae Celastrus Ditto Sepals. Leguminosae *Melilotus! Inflorescence Sepals and petals. Medicago Flower-bud Sepals. Coronilla Ditto Ditto. Trifolium! Ditto Second carpel Pistil. axillary to first Melilotus! Ditto Ditto Trifolium! Flower-bud Sepals and petals. Rosaceae Pyrus! Fruit? Fruit? Cerasus! Flower-bud Petals and stamens. Potentilla! Ditto Leafy carpels. Crataegus! Ditto Petals. *Rosa! Ditto Ditto Sepals, petals, stamens and pistil. Myrtaceae Lecythis Ditto Fruit? Tetragoniaceae Tetragonia? Ditto Ditto. Cactaceae Opuntia! Fruit-like Tufts of spines. branch Pereskia Ditto Sepals? Echinocactus Ditto Ditto. Philadelphaceae Philadelphus Ditto Sepals. Umbelliferae *Athamanta Ditto Calyx. *Daucus! Ditto Calyx and pistil. Bupleurum Ditto Calyx and pistil. Torilis Ditto Calyx and pistil. Apium Flower-bud Calyx and pistil. Pastinaca Ditto Ditto ditto. Heracleum! Ditto Ditto ditto. Angelica! Umbel Ditto ditto. Campanulaceae *Campanula! Branch Sepals. Prismatocarpus Ditto Fruit Sepals, &c. Gentianaceae Gentiana! Flower-bud Sepals. Convolvulaceae *Convolvulus! Ditto Outer calyx. Solanaceae Solanum! Ditto Sepals. Solanum Tubers Sepals and petals. Scrophulariaceae *Digitalis! Ditto Petals, &c. Veronica Raceme Calyx. Primulaceae Anagallis! Branch Ditto Petals. Primula Ditto Petals and carpels. Polygonaceae Rumex Ditto Sepals. Santalaceae Thesium Leaf-bud In place of stamens and pistils, both absent. Euphorbiaceae? Euphorbia? Ditto Outer bracts? Orchidaceae Orchis! Flower-bud Perianth. Amaryllidaceae Leucoium Ditto Ditto. Iridaceae Iris Ditto Pistil. Liliaceae Herreria Ditto Sepals. Hyacinthus Flower and Perianth. raceme Convallaria Flower-bud Ditto. Allium Ditto Ditto. Cyperaceae Carex Inflorescence Utricle.



Complicated prolification.—From what has been before stated it may be seen that prolification of two or more kinds may coexist in the same flower. Mixed leafy and floral prolification is not unfrequent in proliferous roses, where a shoot is, as it were, prolonged through the centre of the original flower and terminated by a second flower, or even by a cluster, as is well shown in the accompanying figure (fig. 67). Median and axillary prolification, also, not unfrequently coexist in the same flower; thus, in a proliferous rose forwarded to me by Mr. W. Thomson (fig. 68), the following changes were observed:—the swollen portion below the calyx, the "hip," was entirely absent; the sepals were leaf-like in aspect, the petals unaffected; above the petals the axis was prolonged for a short distance and then bore a circlet of miniature, sessile roses, destitute, indeed, of calyx, but provided with numerous petals, stamens, and pistils. Above these lateral flowers, the prolonged axis bore a number of scales in many rows. The scales were in their turn surmounted by a whorl of five perfect leaves, beyond which, again, the axis was prolonged into a leafy shoot terminated by a flower bud, the whole constituting a remarkably complicated admixture of elements belonging to the flower, the bud, the inflorescence, and the leafshoot.[143]

Proliferous flowers of Orchids also occasionally present great complexity in the arrangement of their parts. An instance of this kind was described by myself from specimens furnished by Dr. Moore, of Glasnevin, in the 'Journal of the Linnean Society,' vol. ix, p. 349, tabs. x, xi, and from which the following summary is extracted:



The primary flowers were composed of five distinct whorls, and of at least two others less perfectly developed. These primary flowers did not give rise to median formations, but they produced secondary buds in the axils of the segments of the perianth. These latter buds were themselves the subject of tertiary prolification of both kinds, median and axillary. The tertiary median growths, like the primary flower, did not develop median buds, but only lateral ones—quaternary axillary prolification.

The accompanying diagrams are intended to show the plan of arrangement in these flowers. Fig. 69 shows the disposition of parts in the primary flower and the situation of the axillary buds. Fig. 70 shows the primary flower without any central prolongation, but giving off axillary buds, two of which are shown in the diagram, 2, 2; these are, each of them, the subject of both median, 3, 3, and axillary prolification, 4', 4'.



In Narcissus major a similar combination of both forms of prolification exists, as described by Morren.[144]

On the general subject of Prolification in flowers, in addition to the authorities already cited, the reader may refer to the following among many others:

Linnaeus, 'Prolepsis,' Secs. vi et vii. Goethe, 'Versuch. Metamorph.,' cap. xv and xvi Secs. 103-106. Moquin-Tandon,' El. Ter. Veg.,' p. 362, &c. Engelmann, 'De Antholys.,' Secs. 52-62, &c. Cramer, 'Bildungsabweichungen,' &c. Orchidaceae, Umbelliferae, Compositae, Leguminosae, Primulaceae, Ranunculaceae. Fleischer, 'Missbild. Cultur Gewachs.' Schlechtendal, 'Linnaea,' xv, p. 408, Rosa. 'Bot. Zeit.' vol. xx, 1862, p. 382, Cyclamen. 'Bot. Zeit.,' vol. xx, p. 301, Asphodelus; et Lilium. Seringe, 'Bull. Bot.,' i, t. xi, f. 7, 8, Arabis, Diplotaxis. Clos, 'Mem. Acad. Toulouse,' 5th ser., 1862, Papaver. Wigand, 'Flora,' 1856, p. 716, Hypochaeris; et 'Bot. Untersuch.,' p. 19. Buchenau,' Flora,' 1857, p. 295, Reseda. Roeper, 'Bot. Zeit.,' 1852, p. 427, Orchis. Presl., 'Linnaea,' vi, p. 599, tab. ix, figs. 5-8, Sisymbrium, Vrolik., 'Flora,' 1846, p. 97, t. i et ii, id. 1844, t. i, Digitalis. See also Schlechtendal, 'Bot. Zeit.,' vol. ix, 1851, p. 579. Klinsmann, 'Linnaea,' x, p. 604, t. v, Hesperis. Fuckel, 'Flora,' 1848, p. 609. Melilotus. De Candolle, 'Organogr.,' i, 396, t. 33. Turpin, 'Atlas de Goethe,' p. 65, t. 5, figs. 12, 13. Fenzl. 'Sitzungsbericht d. k. Akad. d. Wissensch. Wien.,' heft, iii, tabs. 3, 4, Rosa. Kirschleger, 'Flora,' 1845, 613, Dianthus, Rosa. 'Institut.,' 1841, No. 413, p. 421, Tragopogon. Baron de Melicoq., 'Ann. Sc. Nat.,' 3rd ser., vol. v. 1846, p. 61, Antirrhinum. Reichenbach, 'Icon. Fl. Germ.,' tab. 100, Reseda—"monstrosa anticipatio Euphorbiacearum et Capparidearum." Duhamel, 'Phys. Arbres.,' liv. iii, cap. 3, p. 303, pl. xii, f. 306, Rosa. Caspary, 'Bull. Soc. Bot. Fr.,' vol. vi, 1859, p. 235, Rev. Bibl., Pyrus. Eichler, 'Flora,' 1865, tab. ix, Cleome. Lindley, 'Elements of Botany,' p. 63, &c., Rosa, Epacris, Anagallis, Pyrus. Irmish, 'Flora,' 1858, p. 38, Pyrus; and 'Bot. Zeit.,' xix, 1861, p. 342, Hyacinthus. Duchartre, 'Bull. Soc. Bot. France,' 1861, p. 451, Rosa. Weber, 'Verhandl. Nat. Hist. Verein. Rhein. Preuss., &c.' 1858 et 1860. Landrin, 'Mem. Soc. Sc. Nat. Seine et Oise,' 1866?[145] Masters, 'Trans. Linn. Soc.,' vol. xxiii, p. 359, tab. 34 and p. 481, tab. 54.