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hereafter be described. These rhizomes appear exactly like roots, but occasionally throw up green shoots. They penetrate the earth sometimes to the depth of more than 2 inches; but when the plant grows as an epiphyte, they must creep amidst the mosses, roots, decayed bark, &c., with which the trees of these countries are thickly covered.

As the bladders are attached to the rhizomes, they are necessarily subterranean. They are produced in extraordinary numbers. One of my plants, though young, must have borne several hundreds; for a single branch out of an entangled mass had thirty-two, and another branch, about 2 inches in length (but with its end and one side branch broken off), had seventy-three bladders. The bladders are compressed and rounded, with the ventral surface, or that between the summit of the long delicate footstalk and valve, extremely short (fig. 27). They are colourless and almost as transparent as glass, so that they appear smaller than they really are, the largest being under the of an inch (1.27 mm.) in its longer diameter. They are formed of rather large angular cells, at the junctions of which oblong papillæ project, corresponding with those on the surfaces of the bladders of the previous species. Similar papillæ abound on the rhizomes, and even on the entire leaves, but they are rather broader on the latter. Vessels, marked with parallel bars instead of by a spiral line, run up the footstalks, and

* Prof. Oliver has figured a plant of Utricularia Jamesoniana (Proc. Linn. Soc.' vol. iv. p. 169) having entire leaves and rhizomes, like those of our present species; but the margins of the terminal halves of some of the leaves are converted into bladders. This fact

clearly indicates that the bladders on the rhizomes of the present and following species are modified segments of the leaf; and they are thus brought into accordance with the bladders attached to the divided and floating leaves of the aquatic species.

just enter the bases of the bladders; but they do not bifurcate and extend up the dorsal and ventral surfaces, as in the previous species.

Their

The antennæ are of moderate length, and taper to a fine point; they differ conspicuously from those before described, in not being armed with bristles. bases are so abruptly curved that their tips generally rest one on each side of the middle of the bladder, but

[graphic][subsumed][merged small][merged small]

sometimes near the margin. Their curved bases thus form a roof over the cavity in which the valve lies; but there is always left on each side a little circular passage into the cavity, as may be seen in the drawing, as well as a narrow passage between the bases of the two antennæ. As the bladders are subterranean, had it not been for the roof, the cavity in which the valve lies would have been liable to be blocked up with earth

and rubbish; so that the curvature of the antennæ is a serviceable character. There are no bristles on the outside of the collar or peristome, as in the foregoing species.

The valve is small and steeply inclined, with its free posterior edge abutting against a semicircular, deeply depending collar. It is moderately transparent, and bears two pairs of short stiff bristles, in the same position as in the other species. The presence of these four bristles, in contrast with the absence of those on the antennæ and collar, 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 shapes 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 of an inch (019 mm.) in length; though so small, they act as absorbents. The collar is thick, stiff, and almost semi-circular; it is formed of the same peculiar brownish tissue as in the former species.

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The bladders are filled with water, and sometimes include bubbles of air. They bear internally rather short, thick, quadrifid processes arranged in approximately concentric rows. The two pairs of arms of which they are formed differ only a little 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 includes a small spherical mass of brownish matter, which, when crushed, breaks into angular pieces. I have no doubt that these spheres are nuclei, for closely similar ones

are present in the cells forming the walls of the 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 larger 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 the long bristles on the antennæ 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.

FIG. 28.

(Utricularia montana.)

One of the quadrifid processes; much enlarged.

It seemed to me 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 of an inch (847 mm.) in diameter, 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

or less globular, or fine granules. In distant parts of the same bladder, the processes were transparent and quite empty, with the exception of their solid nuclei. My son made at short intervals of time sketches of one of the above aggregated masses, and found that they continually and completely changed their forms; sometimes separating from one another and again coalescing. Evidently protoplasm had been generated by the absorption of some element from the decaying animal matter.

(2) Another bladder included a still smaller speck of decayed brown matter, and the adjoining quadrifids contained aggregated matter, exactly as in the last case.

(3) A third bladder included a larger organism, which was so much decayed that I could only make out that it was spinose or hairy. The quadrifids in this case were not much affected, excepting that the nuclei in the several arms differed much in size; some of them containing two masses having a similar appearance.

(4) A fourth bladder contained an articulate organism, for I distinctly saw the remnant of a limb, terminating in a hook. The quadrifids were not examined.

(5) A fifth included much decayed matter apparently of some animal, but with no recognisable features. The quadrifids in contact contained numerous spheres of protoplasm.

(6) Some few bladders on the plant which I received from Kew were examined; and in one, there was a worm-shaped animal very little decayed, with a distinct remnant of a similar one greatly decayed. Several of the arms of the processes in contact with these remains contained two spherical masses, like the single solid nucleus which is properly found in each arm. In another bladder there was a minute grain of quartz, reminding me of two similar cases with Utricularia neglecta.

As it appeared probable that this plant would capture a greater number of animals in its native country than under culture, I obtained permission to remove small portions of the rhizomes from dried specimens in the herbarium at Kew. I did not at first find out that it was advisable to soak the rhizomes for two or three days, and that it was necessary to open the bladders and spread out their contents on glass; as from their state of decay and from having been dried and pressed, their nature could not otherwise be well distinguished. Several bladders on a plant which had grown in black earth in New Granada were first examined; and four of these included remnants of animals. The first contained a hairy Acarus, so much decayed that nothing was left except its transparent coat;

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