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Show 434 UTRICULARIA MONTANA. CHAP. XVIII. and rubbish; so that the curvature of the antennoo is a serviceable character. There are no bristles on the outside of the collar or peristome, ~s in the foregoing spec1 s. . . . . . The valve is small and steeply Inchned, WIth 1 ts free posterior edge abutting against a semicircular, deeply depending collar. It is mo~erate~y tran~parent, and bears two pairs of short stiff bnstles, 1n the same position as in the other spe_cies. The presenc.e of these four bi·istles, in contrast with the absence of those on the antennre and collal', indicates that they are of functional importance, namely, as I believe, to prevent too large animals forcing an entrance through the valve. The many glands of diverse shap~s attached to the valve and round the collar in the previous species are here absent, with the exception of about a dozen of the two-armed or transversely elongated kind which are seated near the borders of the valve, and 'are mounted on very short footstalks. These glands are only the 4 o'Jo 0 of an inch (-019 mm.) in length ; though so small, they act as. ~bsorbent~. rfhe collar is thick, stiff, and almost semi-CirCUlar; It is formed of the same peculiar brownish tissue as in the former species. . The bladders are filled with water, anu SOlnetimes include bubbles of air. They bear internally rather short, thick, quadrifid processes arranged in approxiJnately concentric rows. The two p~irs o~ arms of which they are formed differ only a httle In length, and stand in a peculiar position (fig. 28); the two longer ones forming one line, and the two shorter ones another parallel line. Each arm include~ a sn1all spherical mass of brownish matter, which, when crushed breaks into angular pieces. I have no doubt that th~se spheres are nuclei, for closely similar ones CHAP. XVIII. CAPTURED ANIMALS. 435 are present in the cells fonning the walls of th => bladders. Bifid processes, having rather short oval arms, arise in the usual position on the inner side of the collar. These bladders, therefore, resemble in all essential respects. the l~rger ones of the foregoing species. They differ chiefly in the absence of the numerous glands on the valve and round the collar, a few minute ones of one kind alone being present on the valve. They differ more conspicuously in the absence of th long bristles on the an tenure and on the outside of the collar. The presence of these bristles in the previously mentioned species probably relates to the capture of aquatic animals. ~ c:::-~ FrG. 28. ( l..it?·icularia montana.) One of the quadrifid processes; much enlarged. It seemed to n1e an interesting question whether the minute bladders of Utricularia montana served, as in the previous species, to capture animals living in the earth, or in the dense vegetation covering the trees on which this species is epiphytic; for in this case we should have a new sub-class of . carnivorous plants, namely, subterranean feeders. Many bladders, therefore, were examined, with the following results :- (1) A small bladder, less than 31J of an inch ('847 mm.) indiameter, contained a minute mass of brown, much decayed matter; . and in this, a tarsus with four or five joints, terminating in a double hook, was clearly distinguished under the microscope. I suspect that it was a remnant of one of the Thysanoura. The quadrifids in contact with this decayed remnant contained either small masses of translucent, yellowish matter, generally more 2 F 2 |