Insectivorous plants . Fig. 23. {Utricularia vulgaris.) Longitudinal section through a young bladder, -^ of an inch in length, with the orifice too widely open. 426 UTKICULAEIA NEGLECTA. Chap. XYII. must therefore be developed one after the other, andso it wonld be with the two antennee. At a much earlier age, when the half formedbladders are only 3-^ inch (0846 mm.) in diameteror a little more, they present a totally different ap-pearance. One is represented on the left side of theaccompanying drawing (fig. 24). The young leaves. Fig. 24. {Utricularia vulgaris.) Young leaf from a wiuter bud,
Insectivorous plants . Fig. 23. {Utricularia vulgaris.) Longitudinal section through a young bladder, -^ of an inch in length, with the orifice too widely open. 426 UTKICULAEIA NEGLECTA. Chap. XYII. must therefore be developed one after the other, andso it wonld be with the two antennee. At a much earlier age, when the half formedbladders are only 3-^ inch (0846 mm.) in diameteror a little more, they present a totally different ap-pearance. One is represented on the left side of theaccompanying drawing (fig. 24). The young leaves. Fig. 24. {Utricularia vulgaris.) Young leaf from a wiuter bud, showing on the left side a bladder in its earliest stage of development. at this age have broad flattened segments, with theirfuture divisions represented by prominences, one ofwhich is shoT^^l on the right side. Now, in a largenumber of specimens examined by my son, the youngbladders appeared as if formed by the oblique foldingover of the aj)ex and of one margin with a prominence,against the opposite margin. The circular hollowbetween the infolded apex and infolded prominenceapparently contracts into the narrow orifice, whereinthe valve and collar will be developed; the bladderitself being, formed by the confluence of the opposed Chap. XVII. DEVELOPMENT OF THE BLADDEKS. 427 margins of the rest of the leaf. But strong objectionsmay be urged against this view, for we must in thiscase suppose that the valve and collar are developedasymmetrically from the sides of the apex and pro-minence. Moreover, the bundles of vascular ti
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