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Show 426 UTRICULARIA NEGLECTA. CHAP. XVII. must therefore be developed one after the other, and so it would be with the two an tennro. At a much earlier age, when the half formed bladders are only 3 b 0 inch (·0846 mm.) i~ diameter or a little more, they present a totally di~erent appearance. One is represented on the left side of the accompanying drawing (fig. 24). The young leaves FIG. 2-1-. ( Ut?·icularia vulgaTis.) Young l eaf from a winter bud, showing on the left side a bladder in its earliest stage of development. at this acre have broad flattened segments, with their b . f future divisions represented by prominences, one o which is shown on the right side. Now, in a large nun1ber of specimens examined by my so~, the yo~ng bladders appeared as if formed b! th: o bhq ue ~old1ng over of the apex and of one margin with a prominence, against the opposite margin. ~he circular ~ollow between the infolded apex and Infolded prom1nen?e apparently contracts into the narrow orifice, wherem the valve and collar will be developed ; the bladder itself being formed by the confluence of the opposed 0IIAP. XVII. DEVELOPMENT OF THE BLADDERS. 427 margins of the rest_ of the_ lea~. But strong objections 1nay be urged against this view, for we must in this case supp?se that the valve and collar are developed as!mmetncally from the sides of the apex and prominence. Moreover, the bundles of vascular tissue h~v~ to be formed in lines quite irrespective of the onginal form of the leaf. Until gradations can be shown to exist between this the earliest state and a young yet perfect bladder, the case must be left doubtful. As the quadrifid and bifid processes offer one of the gre~test peculiarities in the genus, I carefully observed then development in Utricularia neglecta. In bladders about T&o of an inch in diameter, the inner surface is studded with papillre, rising froin small cells at the junctions of the larger ones. These papillre consist of a delicate conical protuberance, which narrows into a very short footstalk, surmounted by two minute cells. They thus occupy the same relative position, and closely resemble, except in being smaller and rather more prominent, the papillre on the outside of the bladders, and on the surfaces of the leaves. The two terminal cells of the papillre first become much elongated in a line parallel to the inner surface of the bladder. Next, each is divided by a longitudinal partition. Soon the two half-cells thus formed separate from one another; and we now have four cells or an incipient quadrifid process. As there is not space for the two new cells to increase in breadth in their original plane, the one slides partly under the other. Their manner of growth· now changes, and their outer sides, instead of their apices, continue to grow. The two lower cells, which have slid partly beneath the two upper ones, form the longer and more upright pair of processes; whilst the two upper cells form the shorter |