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Show 438 UTRICULARIA MONTANA. CHAP. XVIII. other sinall; and in others there were irregularly shaped globules ; so that it appeared as if the lin1pid contents of the processes, owing to the absorption of 1natter from the solution, had become aggregated smnetimes round the nucleus, and sometimes into separate masses; and that these then tended to eoalesce. The priinordial utricle or protoplasm lining the processes was also thickened here and there in to irregular and variously shaped specks of yellowish translucent matter, as occurred in the case of Utricularia neglecta under siinilar treat1nent. These specks apparently did not change their forms. The n1inute two-armed glands on the valve were also affected by the solution; for they now contained several, sometimes as many as six or eight, almost spherical masses of translucent 1natter, tinged with yellow, which slowly changed their forms and positions. Such masses were never observed in these glands in their ordinary state. We may therefore infer that they serve for absorption. Whenever a little water is expelled from a bladder containing animal remains (by the means formerly specified, more especially by the generation of bubbles of air), it will fill the cavity in which the valve lies; and thus the glands will be able to utilise decayed matter which otherwise would hav been wasted. Finally, as numerous minute animals are captured by this plant in its native country and when cultivated, there can be no doubt that the bladders, though so small, are far from being in a rudiinentary condition ; on the contrary, they are highly effi.cient traps. Nor can there be any doubt that matter is absorbed from the decayed prey by the quadrifid and bifid processes, and that protoplasm is thus generated. vVhat tempts animals of such diverse kinds to enter CHAP. XVIII. HESERVOIRS FOR vVATER. 439 the. cavity ben oath the bowed antennre, and then force then way through the little slit-like orifice betwe n tho valve and collar into the bladders filled with water, I cannot conjecture. . Tubers.- . These organs, one of which is represented In a previous figure (fig. 26) of the natural size deserve a few remarks. Twenty were found on th ' rhizomes of a sin~le plant, but they cannot be strictly c?unted; foi:, besides the twenty, there were all possible gradations between a short length of a rhizon1o just perceptibly swollen and one so much swollen that it Inight be doubtfully called a tuber. vVhen well developed, they are oval and symmetrical, Inore so than appears in the figure. The laraest which I saw was 1 inch (25·4 mm.) in length 0 ancl ·45 inch (11·43 mm.) in breadth. They commonly lie near the surface, but some are buried at the depth of 2 inches. The buried ones are dirty white, but those partly exposed to the light become greenish from tho development, of chlorophyll in their superficial cells. They terminate in a rhizome, but this sometimes decays and drops off. They do not contain any air, and they sink in water; their surfaces are covered with the usual papillre. The bundle of vessels which runs up each rhizome, as soon as it enters the tuber, separates into three distinct bundles, which reunite at the opposite end. A rather thick slice of a tuber is almost as transparent as glass, and is seen to consist of large angular cells, full of water and not containing starch or any other solid matter. Some slices were left in alcohol for several days, but . only a few ex..t~·emely minute granules of matter were precipitated on the ·walls of the cells ; and these were much smaller and fewer than those precipitated on the cell-walls of the rhizomes and bladders. We may therefore con- |