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Show 432 UTRICULARIA MONTANA. CHAP. XVIII. hereafter be described. These rhizomes appear exactly like roots, but occasionally throw up green shoots. They penetrate the earth sometim.es to the depth of more than 2 inches; but when the plant grows as an epiphyte, they must creep a1nidst the 1nosses, roots, decayed bark, &c., with which the trees of these conn tries 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 com pressed and rounded, with the ventral surface, or that between the sun11nit 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 Q 1 0 of an inch (1·27 mm.) in its longer diameter. They are formed of rather large angular cells, at the junctions of which oblong papillre project, corresponding with those on the surfaces of the bladders of the previous species. Similar papillre abound on the rhizomes, and even on the en tire 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 Utricula1·ia 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 conYertcd into bladders. rrhis 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. CHAP. XVIII~ STRUCTURE OF THE BLADDERS. 433 j~st enter the bases of the bladders,· but b f t they do not f 1 urea e · and extend up the d orsa l an d ventral sur-aces, as In the previous species. fin~h:tn~ennre ar~ of mode~ate length, and taper to a d ~ nt' _they differ conspicuously from those b fore escn bed, In not being armed with bristles Th . , bases are so abruptlv curved that th .. t' . ~11' J en 1ps generally rest one on each side of the middle of the bladder, c.bnt • Frc. 2'7. ( l:t1·ict~la1·ia montana.) Bladder; al>out 2'7 times enlarged. ~o~etimes near the marg~n. Their curved bases thus orm a roo_f over the cavity in which the valve lies. but ther_e IS always left on each side a little circnlal: passage Into the cavity, as may be seen in the drawin~ as well as a narrow passage between the bases of th~ ~wo an tennre. As the bladders are subterranean, had I~ not been for the roof, the cavity in which the valve hes would have been liable to be blocked up with earth 2 F |