Polypompholyx tenella.—The bladders are smaller than those of the last species, but have the same general structure. They were full of dbris, apparently organic, but no remains of articulate animals could be distinguished.

* 'Proc. Linn. Soc.' vol. iv. p. 171. [page 446]

GENLISEA.

This remarkable genus is technically distinguished from Utricularia, as I hear from Prof. Oliver, by having a five-partite calyx. Species are found in several parts of the world, and are said to be "herbae annuae paludosae."

Genlisea ornata (Brazil).—This species has been described and figured by Dr. Warming,* who states that it bears two kinds of leaves, called by him spathulate and utriculiferous. The latter include cavities; and as these differ much from the bladders of the foregoing species, it will be convenient to speak of them as utricles. The accompanying figure (fig. 29) of one of the utriculiferous leaves, about thrice enlarged, will illustrate the following description by my son, which agrees in all essential points with that given by Dr. Warming. The utricle (b) is formed by a slight enlargement of the narrow blade of the leaf. A hollow neck (n), no less than fifteen times as long as the utricle itself, forms a passage from the transverse slit-like orifice (o) into the cavity of the utricle. A utricle which measured 1/36 of an inch (.705 mm.,) in its longer diameter had a neck 15/36 (10.583 mm.) in length, and 1/100 of an inch (.254 mm.) in breadth. On each side of the orifice there is a long spiral arm or tube (a); the structure of which will be best understood by the following illustration. Take a narrow ribbon and wind it spirally round a thin cylinder, so that the edges come into contact along its whole length; then pinch up the two edges so as to form a little crest, which will of course wind spirally

* "Bidrag til Kundskaben om Lentibulariaceae," Copenhagen 1874. [page 447]

round the cylinder like a thread round a screw. If the cylinder is now removed, we shall have a tube like one of the spiral arms. The two projecting edges are not actually united, and a needle can be pushed in easily between them. They are indeed in many places a little separated, forming narrow entrances into the tube; but this may be the result of the drying of the specimens. The lamina of which the tube is formed seems to be a lateral prolongation of the lip of the orifice; and the spiral line between the two projecting edges is continuous with the corner of the orifice. If a fine bristle is pushed down one of the arms, it passes into the top of the hollow neck. Whether the arms are open or closed at their extremities could not be determined, as all the specimens were broken; nor does it appear that Dr. Warming ascertained this point.

FIG. 29. (Genlisea ornata.) Utriculiferous leaf; enlarged about three times. l Upper part of lamina of leaf. b Utricle or bladder. n Neck of utricle. o Orifice. a Spirally wound arms, with their ends broken off.

So much for the external structure. Internally the lower part of the utricle is covered with spherical papillae, formed of four cells (sometimes eight according to Dr. Warming), which evidently answer to the quadrifid processes within the bladders of Utricularia. [page 448] These papillae extend a little way up the dorsal and ventral surfaces of the utricle; and a few, according to Warming, may be found in the upper part. This upper region is covered by many transverse rows, one above the other, of short, closely approximate hairs, pointing downwards. These hairs have broad bases, and their tips are formed by a separate cell. They are absent in the lower part of the utricle where the papillae abound.

FIG. 30. (Genlisea ornata.) Portion of inside of neck leading into the utricle, greatly enlarged, showing the downward pointed bristles, and small quadrifid cells or processes.

The neck is likewise lined throughout its whole length with transverse rows of long, thin, transparent hairs, having broad bulbous (fig. 30) bases, with similarly constructed sharp points. They arise from little projecting ridges, formed of rectangular epidermic cells. The hairs vary a little in length, but their points generally extend down to the row next below; so that if the neck is split open and laid flat, the inner surface resembles a paper of pins,—the hairs representing the pins, and the little transverse ridges representing the folds of paper through which the pins are thrust. These rows of hairs are indicated in the previous figure (29) by numerous transverse lines crossing the neck. The inside of the neck is [page 449] also studded with papillae; those in the lower part are spherical and formed of four cells, as in the lower part of the utricle; those in the upper part are formed of two cells, which are much elongated downwards beneath their points of attachment. These two-celled papillae apparently correspond with the bifid process in the upper part of the bladders of Utricularia. The narrow transverse orifice (o, fig. 29) is situated between the bases of the two spiral arms. No valve could be detected here, nor was any such structure seen by Dr. Warming. The lips of the orifice are armed with many short, thick, sharply pointed, somewhat incurved hairs or teeth.

The two projecting edges of the spirally wound lamina, forming the arms, are provided with short incurved hairs or teeth, exactly like those on the lips. These project inwards at right angles to the spiral line of junction between the two edges. The inner surface of the lamina supports two-celled, elongated papillae, resembling those in the upper part of the neck, but differing slightly from them, according to Warming, in their footstalks being formed by prolongations of large epidermic cells; whereas the papillae within the neck rest on small cells sunk amidst the larger ones. These spiral arms form a conspicuous difference between the present genus and Utricularia.

Lastly, there is a bundle of spiral vessels which, running up the lower part of the linear leaf, divides close beneath the utricle. One branch extends up the dorsal and the other up the ventral side of both the utricle and neck. Of these two branches, one enters one spiral arm, and the other branch the other arm.

The utricles contained much dbris or dirty matter, which seemed organic, though no distinct organisms [page 450] could be recognised. It is, indeed, scarcely possible that any object could enter the small orifice and pass down the long narrow neck, except a living creature. Within the necks, however, of some specimens, a worm with retracted horny jaws, the abdomen of some articulate animal, and specks of dirt, probably the remnants of other minute creatures, were found. Many of the papillae within both the utricles and necks were discoloured, as if they had absorbed matter.

From this description it is sufficiently obvious how Genlisea secures its prey. Small animals entering the narrow orifice—but what induces them to enter is not known any more than in the case of Utricularia—would find their egress rendered difficult by the sharp incurved hairs on the lips, and as soon as they passed some way down the neck, it would be scarcely possible for them to return, owing to the many transverse rows of long, straight, downward pointing hairs, together with the ridges from which these project. Such creatures would, therefore, perish either within the neck or utricle; and the quadrifid and bifid papillae would absorb matter from their decayed remains. The transverse rows of hairs are so numerous that they seem superfluous merely for the sake of preventing the escape of prey, and as they are thin and delicate, they probably serve as additional absorbents, in the same manner as the flexible bristles on the infolded margins of the leaves of Aldrovanda. The spiral arms no doubt act as accessory traps. Until fresh leaves are examined, it cannot be told whether the line of junction of the spirally wound lamina is a little open along its whole course, or only in parts, but a small creature which forced its way into the tube at any point, would be prevented from escaping by the incurved hairs, and would find an open path down [page 451] the tube into the neck, and so into the utricle. If the creature perished within the spiral arms, its decaying remains would be absorbed and utilised by the bifid papillae. We thus see that animals are captured by Genlisea, not by means of an elastic valve, as with the foregoing species, but by a contrivance resembling an eel-trap, though more complex.

Genlisea africana (South Africa).—Fragments of the utriculiferous leaves of this species exhibited the same structure as those of Genlisea ornata. A nearly perfect Acarus was found within the utricle or neck of one leaf, but in which of the two was not recorded.

Genlisea aurea (Brazil).—A fragment of the neck of a utricle was lined with transverse rows of hairs, and was furnished with elongated papillae, exactly like those within the neck of Genlisea ornata. It is probable, therefore, that the whole utricle is similarly constructed.

Genlisea filiformis (Bahia, Brazil).—Many leaves were examined and none were found provided with utricles, whereas such leaves were found without difficulty in the three previous species. On the other hand, the rhizomes bear bladders resembling in essential character those on the rhizomes of Utricularia. These bladders are transparent, and very small, viz. Only 1/100 of an inch (.254 mm.) in length. The antennae are not united at their bases, and apparently bear some long hairs. On the outside of the bladders there are only a few papillae, and internally very few quadrifid processes. These latter, however, are of unusually large size, relatively to the bladder, with the four divergent arms of equal length. No prey could be seen within these minute bladders. As the rhizomes of this species were furnished with bladders, those of Genlisea africana, ornata, and aurea were carefully [page 452] examined, but none could be found. What are we to infer from these facts? Did the three species just named, like their close allies, the several species of Utricularia, aboriginally possess bladders on their rhizomes, which they afterwards lost, acquiring in their place utriculiferous leaves? In support of this view it may be urged that the bladders of Genlisea filiformis appear from their small size and from the fewness of their quadrifid processes to be tending towards abortion; but why has not this species acquired utriculiferous leaves, like its congeners?

CONCLUSION.—It has now been shown that many species of Utricularia and of two closely allied genera, inhabiting the most distant parts of the world—Europe, Africa, India, the Malay Archipelago, Australia, North and South America—are admirably adapted for capturing by two methods small aquatic or terrestrial animals, and that they absorb the products of their decay.

Ordinary plants of the higher classes procure the requisite inorganic elements from the soil by means of their roots, and absorb carbonic acid from the atmosphere by means of their leaves and stems. But we have seen in a previous part of this work that there is a class of plants which digest and afterwards absorb animal matter, namely, all the Droseraceae, Pinguicula, and, as discovered by Dr. Hooker, Nepenthes, and to this class other species will almost certainly soon be added. These plants can dissolve matter out of certain vegetable substances, such as pollen, seeds, and bits of leaves. No doubt their glands likewise absorb the salts of ammonia brought to them by the rain. It has also been shown that some other plants can absorb ammonia by [page 453] their glandular hairs; and these will profit by that brought to them by the rain. There is a second class of plants which, as we have just seen, cannot digest, but absorb the products of the decay of the animals which they capture, namely, Utricularia and its close allies; and from the excellent observations of Dr. Mellichamp and Dr. Canby, there can scarcely be a doubt that Sarracenia and Darlingtonia may be added to this class, though the fact can hardly be considered as yet fully proved. There is a third class of plants which feed, as is now generally admitted, on the products of the decay of vegetable matter, such as the bird's-nest orchis (Neottia), &c. Lastly, there is the well-known fourth class of parasites (such as the mistletoe), which are nourished by the juices of living plants. Most, however, of the plants belonging to these four classes obtain part of their carbon, like ordinary species, from the atmosphere. Such are the diversified means, as far as at present known, by which higher plants gain their subsistence.

[page 454]

[page 455]



INDEX.

ABSORPTION—AMMONIA.

A.

ABSORPTION by Dionaea, 295 — by Drosera, 17 — by Drosophyllum, 337 — by Pinguicula, 381 — by glandular hairs, 344 — by glands of Utricularia, 416, 421 — by quadrifids of Utricularia, 413, 421 — by Utricularia montana, 437

Acid, nature of, in digestive secretion of Drosera, 88 — present in digestive fluid of various species of Drosera, Dionaea, Drosophyllum, and Pinguicula, 278, 301, 339, 381

Acids, various, action of, on Drosera, 188 — of the acetic series replacing hydrochloric in digestion, 89 —, arsenious and chromic, action on Drosera, 185 —, diluted, inducing negative osmose, 197

Adder's poison, action on Drosera, 206

Aggregation of protoplasm in Drosera, 38 — in Drosera induced by salts of ammonia, 43 — — caused by small doses of carbonate of ammonia, 145 — of protoplasm in Drosera, a reflex action, 242 — — in various species of Drosera, 278 — — in Dionaea, 290, 300

Aggregation of protoplasm in Drosophyllum, 337, 339 — — in Pinguicula, 370, 389 — — in Utricularia, 411, 415, 429, 430, 436

Albumen, digested by Drosera, 92 —, liquid, action on Drosera, 79

Alcohol, diluted, action of, on Drosera, 78, 216

Aldrovanda vesiculosa, 321 —, absorption and digestion by, 325 —, varieties of, 329

Algae, aggregation in fronds of, 65

Alkalies, arrest digestive process in Drosera, 94

Aluminium, salts of, action on Drosera, 184

Ammonia, amount of, in rain water, 172 —, carbonate, action on heated leaves of Drosera, 69 —, —, smallness of doses causing aggregation in Drosera, 145 —, —, its action on Drosera, 141 —, —, vapour of, absorbed by glands of Drosera, 142 —, —, smallness of doses causing inflection in Drosera, 145, 168 —, phosphate, smallness of doses causing inflection in Drosera, 153, 168 —, —, size of particles affecting Drosera, 173 —, nitrate, smallness of doses causing inflection in Drosera, 148, 168 —, salts of, action on Drosera, 136 [page 456]

AMMONIA—CURTIS.

Ammonia, salts of, their action affected by previous immersion in water and various solutions, 213 —, —, induce aggregation in Drosera, 43 —, various salts of, causing inflection in Drosera, 166

Antimony, tartrate, action on Drosera, 185

Areolar tissue, its digestion by Drosera, 102

Arsenious acid, action on Drosera, 185

Atropine, action on Drosera, 204

B.

Barium, salts of, action on Drosera, 183

Bases of salts, preponderant action of, on Drosera, 186

Basis, fibrous, of bone, its digestion by Drosera, 108

Belladonna, extract of, action on Drosera, 84

Bennett, Mr. A.W., on Drosera, 2 —, coats of pollen-grains not digested by insects, 117

Binz, on action of quinine on white blood-corpuscles, 201 —, on poisonous action of quinine on low organisms, 202

Bone, its digestion by Drosera, 105

Brunton, Lauder, on digestion of gelatine, 111 —, on the composition of casein, 115 —, on the digestion of urea, 124 —, — of chlorophyll, 126 —, — of pepsin, 124

Byblis, 343

C.

Cabbage, decoction of, action on Drosera, 83

Cadmium chloride, action on Drosera, 183

Caesium, chloride of, action on Drosera, 181

Calcium, salts of, action on Drosera, 182

Camphor, action on Drosera, 209

Canby, Dr., on Dionaea, 301, 310, 313 —, on Drosera filiformis, 281

Caraway, oil of, action on Drosera, 211

Carbonic acid, action on Drosera, 221 —, delays aggregation in Drosera, 59

Cartilage, its digestion by Drosera, 103

Casein, its digestion by Drosera, 114

Cellulose, not digested by Drosera, 125

Chalk, precipitated, causing inflection of Drosera, 32

Cheese, its digestion by Drosera, 116

Chitine, not digested by Drosera, 124

Chloroform, effects of, on Drosera, 217 —, —, on Dionaea, 304

Chlorophyll, grains of, in living plants, digested by Drosera, 126 —, pure, not digested by Drosera, 125

Chondrin, its digestion by Drosera, 112

Chromic acid, action on Drosera, 185

Cloves, oil of, action on Drosera, 212

Cobalt chloride, action on Drosera, 186

Cobra poison, action on Drosera, 206

Cohn, Prof., on Aldrovanda, 321 —, on contractile tissues in plants, 364 —, on movements of stamens of Compositae, 256 —, on Utricularia, 395

Colchicine, action on Drosera, 204

Copper chloride, action on Drosera, 185

Crystallin, its digestion by Drosera, 120

Curare, action on Drosera, 204

Curtis, Dr., on Dionaea, 301 [page 457]

DARWIN—FIBROUS.

D.

Darwin, Francis, on the effect of an induced galvanic current on Drosera, 37 —, on the digestion of grains of chlorophyll, 126 —, on Utricularia, 442

Delpino, on Aldrovanda, 321 —, on Utricularia, 395

Dentine, its digestion by Drosera, 106

Digestion of various substances by Dionaea, 301 — — by Drosera, 85 — — by Drosophyllum, 339 — — by Pinguicula, 381 —, origin of power of, 361

Digitaline, action on Drosera, 203

Dionaea muscipula, small size of roots, 286 —, structure of leaves, 287 —, sensitiveness of filaments, 289 —, absorption by, 295 —, secretion by, 295 —, digestion by, 301 —, effects on, of chloroform, 304 —, manner of capturing insects, 305 —, transmission of motor impulse, 313 —, re-expansion of lobes, 318

Direction of inflected tentacles of Drosera, 243

Dohrn, Dr., on rhizocephalous crustaceans, 357

Donders, Prof., small amount of atropine affecting the iris of the dog, 172

Dragonfly caught by Drosera, 2

Drosera anglica, 278 — binata, vel dichotoma, 281 — capensis, 279 — filiformis, 281 — heterophylla, 284 — intermedia, 279

Drosera rotundifolia, structure of leaves, 4 —, effects on, of nitrogenous fluids, 76 Drosera rotundifolia, effects of heat on, 66 —, its power of digestion, 85 —, backs of leaves not sensitive, 231 —, transmission of motor impulse, 234 —, general summary, 262 — spathulata, 280

Droseraceae, concluding remarks on, 355 —, their sensitiveness compared with that of animals, 366

Drosophyllum, structure of leaves, 333 —, secretion by, 334 —, absorption by, 337 —, digestion by, 339

E.

Enamel, its digestion by Drosera, 106

Erica tetralix, glandular hairs of, 351

Ether, effects of, on Drosera, 219 —, —, on Dionaea, 304

Euphorbia, process of aggregation in roots of, 63

Exosmose from backs of leaves of Drosera, 231

F.

Fat not digested by Drosera, 126

Fayrer, Dr., on the nature of cobra poison, 206 —, on the action of cobra poison on animal protoplasm, 208 —, on cobra poison paralysing nerve centres, 224

Ferment, nature of, in secretion of Drosera, 94, 97

Fibrin, its digestion by Drosera, 100

Fibro-cartilage, its digestion by Drosera, 104

Fibro-elastic tissue, not digested by Drosera, 122

Fibrous basis of bone, its digestion by Drosera, 108 [page 458]

FLUIDS—LEAVES.

Fluids, nitrogenous, effects of, on Drosera, 76

Fournier, on acids causing movements in stamens of Berberis, 196

Frankland, Prof., on nature of acid in secretion of Drosera, 88

G.

Galvanism, current of, causing inflection of Drosera, 37 —, effects of, on Dionaea, 318

Gardner, Mr., on Utricularia nelumbifolia, 442

Gelatin, impure, action on Drosera, 80 —, pure, its digestion by Drosera, 110

Genlisea africana, 451 — filiformis, 451

Genlisea ornata, structure of, 446 —, manner of capturing prey, 450

Glandular hairs, absorption by, 344 —, summary on, 353

Globulin, its digestion by Drosera, 120

Gluten, its digestion by Drosera, 117

Glycerine, inducing aggregation in Drosera, 52 —, action on Drosera, 212

Gold chloride, action on Drosera, 184

Gorup-Besanez on the presence of a solvent in seeds of the vetch, 362

Grass, decoction of, action on Drosera, 84

Gray, Asa, on the Droseraceae, 2

Groenland, on Drosera, 1, 5

Gum, action of, on Drosera, 77

Gun-cotton, not digested by Drosera, 125

H.

Haematin, its digestion by Drosera, 121

Hairs, glandular, absorption by, 344 —, —, summary on, 353

Heat, inducing aggregation in Drosera, 53 —, effect of, on Drosera, 66 —, —, on Dionaea, 294, 319

Heckel, on state of stamens of Berberis after excitement, 43

Hofmeister, on pressure arresting movements of protoplasm, 61

Holland, Mr., on Utricularia, 395

Hooker, Dr., on carnivorous plants, 2 —, on power of digestion by Nepenthes, 97 —, history of observations on Dionaea, 286

Hydrocyanic acid, effects of, on Dionaea, 305

Hyoscyamus, action on Drosera, 84, 206

I.

Iron chloride, action on Drosera, 185

Isinglass, solution of, action on Drosera, 80

J.

Johnson, Dr., on movement of flower-stems of Pinguicula, 381

K.

Klein, Dr., on microscopic character of half digested bone, 106 —, on state of half digested fibro-cartilage, 104 —, on size of micrococci, 173

Knight, Mr., on feeding Dionaea, 301

Kossmann, Dr., on rhizocephalous crustaceans, 357

L.

Lead chloride, action on Drosera, 184

Leaves of Drosera, backs of, not sensitive, 231 [page 459]

LEGUMIN—PINGUICULA.

Legumin, its digestion by Drosera, 116

Lemna, aggregation in leaves of, 64

Lime, carbonate of, precipitated, causing inflection of Drosera, 32 —, phosphate of, its action on Drosera, 109

Lithium, salts of, action on Drosera, 181

M.

Magnesium, salts of, action on Drosera, 182

Manganese chloride, action on Drosera, 185

Marshall, Mr. W., on Pinguicula, 369

Means of movement in Dionaea, 313 — in Drosera, 254

Meat, infusion of, causing aggregation in Drosera, 51 —, —, action on Drosera, 79 —, its digestion by Drosera, 98

Mercury perchloride, action on Drosera, 183

Milk, inducing aggregation in Drosera, 51 —, action on Drosera, 79 —, its digestion by Drosera, 113

Mirabilis longiflora, glandular hairs of, 352

Moggridge, Traherne, on acids injuring seeds, 128

Moore, Dr., on Pinguicula, 390

Morphia acetate, action on Drosera, 205

Motor impulse in Drosera, 234, 258 — in Dionaea, 313

Movement, origin of power of, 363

Movements of leaves of Pinguicula, 371 — of tentacles of Drosera, means of, 254 — of Dionaea, means of, 313

Mucin, not digested by Drosera, 122

Mucus, action on Drosera, 80

Mller, Fritz, on rhizocephalous crustaceans, 357

N.

Nepenthes, its power of digestion, 97

Nickel chloride, action on Drosera, 186

Nicotiana tabacum, glandular hairs of, 352

Nicotine, action on Drosera, 203

Nitric ether, action on Drosera, 220

Nitschke, Dr., references to his papers on Drosera, 1 —, on sensitiveness of backs of leaves of Drosera, 231 —, on direction of inflected tentacles in Drosera, 244 —, on Aldrovanda, 322

Nourishment, various means of, by plants, 452

Nuttall, Dr., on re-expansion of Dionaea, 318

O.

Odour of pepsin, emitted from leaves of Drosera, 88

Oil, olive, action of, on Drosera, 78, 126

Oliver, Prof., on Utricularia, 432, 441-446

P.

Papaw, juice of, hastening putrefaction, 411

Particles, minute size of, causing inflection in Drosera, 27, 32

Peas, decoction of, action on Drosera, 82

Pelargonium zonale, glandular hairs of, 350

Pepsin, odour of, emitted from Drosera leaves, 88 —, not digested by Drosera, 123 —, its secretion by animals excited only after absorption, 129

Peptogenes, 129

Pinguicula grandiflora, 390 — lusitanica, 391 [page 460]

PINGUICULA—SAXIFRAGA.

Pinguicula vulgaris, structure of leaves and roots, 368 —, number of insects caught by, 369 —, power of movement, 371 —, secretion and absorption by, 381 —, digestion by, 381 —, effects of secretion on living seeds, 390

Platinum chloride, action on Drosera, 186

Poison of cobra and adder, their action on Drosera, 206

Pollen, its digestion by Drosera, 117

Polypompholyx, structure of, 445

Potassium, salts of, inducing aggregation in Drosera, 50 —, —, action on Drosera, 179 — phosphate, not decomposed by Drosera, 180, 187

Price, Mr. John, on Utricularia, 429

Primula sinensis, glandular hairs of, 348 —, number of glandular hairs of, 355

Protoplasm, aggregation of, in Drosera, 38 —, —, in Drosera, caused by small doses of carbonate of ammonia, 145 —, —, in Drosera, a reflex action, 242 — aggregated, re-dissolution of, 53 —, aggregation of, in various species of Drosera, 278 —, —, in Dionaea, 290, 300 —, —, in Drosophyllum, 337, 339 —, —, in Pinguicula, 370, 389 —, —, in Utricularia, 411, 415, 429, 430, 436

Q.

Quinine, salts of, action on Drosera, 201

R.

Rain-water, amount of ammonia in, 172

Ralfs, Mr., on Pinguicula, 390

Ransom, Dr., action of poisons on the yolk of eggs, 225

Re-expansion of headless tentacles of Drosera, 229 — of tentacles of Drosera, 260 — of Dionaea, 318

Roots of Drosera, 18 — of Drosera, process of aggregation in, 63 — of Drosera, absorb carbonate of ammonia, 141 — of Dionaea, 286 — of Drosophyllum, 332 — of Pinguicula, 369

Roridula, 342

Rubidium chloride, action on Drosera, 181

S.

Sachs, Prof., effects of heat on protoplasm, 66, 70 —, on the dissolution of proteid compounds in the tissues of plants, 362

Saliva, action on Drosera, 80

Salts and acids, various, effects of, on subsequent action of ammonia, 214

Sanderson, Burdon, on coagulation of albumen from heat, 74 —, on acids replacing hydrochloric in digestion, 89 —, on the digestion of fibrous basis of bone, 108 —, — of gluten, 118 —, — of globulin, 120 —, — of chlorophyll, 126 —, on different effect of sodium and potassium on animals, 187 —, on electric currents in Dionaea, 318

Saxifraga umbrosa, glandular hairs of, 345 [page 461]

SCHIFF—TURPENTINE.

Schiff, on hydrochloric acid dissolving coagulated albumen, 86 —, on manner of digestion of albumen, 93 —, on changes in meat during digestion, 99 —, on the coagulation of milk, 114 —, on the digestion of casein, 116 —, — of mucus, 123 —, on peptogenes, 129

Schloesing, on absorption of nitrogen by Nicotiana, 352

Scott, Mr., on Drosera, 1

Secretion of Drosera, general account of, 13 — —, its antiseptic power, 15 — —, becomes acid from excitement, 86 — —, nature of its ferment, 94, 97 — by Dionaea, 295 — by Drosophyllum, 335 — by Pinguicula, 381

Seeds, living, acted on by Drosera, 127 —, —, acted on by Pinguicula, 385, 390

Sensitiveness, localisation of, in Drosera, 229 — of Dionaea, 289 — of Pinguicula, 371

Silver nitrate, action on Drosera, 181

Sodium, salts of, action on Drosera, 176 —, —, inducing aggregation in Drosera, 50

Sondera heterophylla, 284

Sorby, Mr., on colouring matter of Drosera, 5

Spectroscope, its power compared with that of Drosera, 170

Starch, action of, on Drosera, 78, 126

Stein, on Aldrovanda, 321

Strontium, salts of, action on Drosera, 183

Strychnine, salts of, action on Drosera, 199

Sugar, solution of, action of, on Drosera, 78 —, —, inducing aggregation in Drosera, 51

Sulphuric ether, action on Drosera, 219 —, — on Dionaea, 304

Syntonin, its action on Drosera, 102

T.

Tait, Mr., on Drosophyllum, 332

Taylor, Alfred, on the detection of minute doses of poisons, 170

Tea, infusion of, action on Drosera, 78

Tentacles of Drosera, move when glands cut of, 36, 229 —, inflection, direction of, 243 —, means of movement, 254 —, re-expansion of, 260

Theine, action on Drosera, 204

Tin chloride, action on Drosera, 185

Tissue, areolar, its digestion by Drosera, 102 —, fibro-elastic, not digested by Drosera, 122

Tissues through which impulse is transmitted in Drosera, 247 — — in Dionaea, 313

Touches repeated, causing inflection in Drosera, 34

Transmission of motor impulse in Drosera, 234 — — in Dionaea, 313

Traube, Dr., on artificial cells, 216

Treat, Mrs., on Drosera filiformis, 281 —, on Dionaea, 311 —, on Utricularia, 408, 430

Trcul, on Drosera, 1, 5

Tubers of Utricularia montana, 439

Turpentine, action on Drosera, 212 [page 462]

UREA—ZINC.

U.

Urea, not digested by Drosera, 124

Urine, action on Drosera, 79

Utricularia clandestina, 430 — minor, 429

Utricularia montana, structure of bladders, 431 —, animals caught by, 435 —, absorption by, 437 —, tubers of, serving as reservoirs, 439

Utricularia neglecta, structure of bladders, 397 —, animals caught by, 405 —, absorption by, 413 —, summary on absorption, 421 —, development of bladders, 424

Utricularia, various species of, 441

Utricularia vulgaris, 428

V.

Veratrine, action on Drosera, 204

Vessels in leaves of Drosera, 247 — of Dionaea, 314

Vogel, on effects of camphor on plants, 209

W.

Warming, Dr., on Drosera, 2, 6 —, on roots of Utricularia, 397 —, on trichomes, 359 —, on Genlisea, 446 —, on parenchymatous cells in tentacles of Drosera, 252

Water, drops of, not causing inflection in Drosera, 35 —, its power in causing aggregation in Drosera, 52 —, its power in causing inflection in Drosera, 139 — and various solutions, effects of, on subsequent action of ammonia, 213

Wilkinson, Rev., on Utricularia, 398

Z.

Ziegler, his statements with respect to Drosera, 23 —, experiments by cutting vessels of Drosera, 249

Zinc chloride, action on Drosera, 184

THE END