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Show 424 UTRICULARIA NEGLECTA. CHAP. XVII. ammonia, fro1n a putrid infusion of raw meat, and frmn urea. The glands apparently are acted on more strongly by a solution of urea, and less strongly by an infusion of raw meat, than are the processes. rrhe case of urea is particularly interesting, because we have seen that it produces no effect on Drosera, the 1 aves of which are adapted to digest fresh animal 111atter. But the most important fact of all is, that in the present and following species . t~e quadrifid and bifid processes of bladders conta1n1ng decayed anilnals O'enerally include little masses of spontaneous! y m~ving protoplasm ; whilst such masses are never seen in perfectly clean bladders. Development of the Bladders.-My son and I spent 1nuch time over this subject with small success. Our observations apply to the present species and to Utricularia vulgaris, but were made chiefly on the l~tter, ~s the bladders are twice as large as those of Utrwular~a neglecta. In the early pa~t of autumn the. stems terminate in large buds, wh1ch fall off and he dormant · during the winter at the bottom .. The !oung leaves forming these buds bear bladders 1n vanous s~ages ?f early development. When the bladders of. Utr~cular~a vulgaris are about 1 b 0 inch (·254 mm.) 1n diameter (or _ 1_ in the case of Utricula'ria neglecta ), they are ~ 0 0 circular in outline, with a narrow, almost closed, trans-verse orifice, leading into a hollow filled with water; but the bladders are hollow when much und.er Th of an inch in diameter. rrhe orifices face inwards or towards the axis of the plant. At this early age the bladders are flattened in the plane in which the orifice lies and therefore at right angles to that of the ma~ure bladders. They are covered exteriorly with papillre of different sizes, many of which have an elliptical outlin~. A bundle of vessels, formed of CHAP. XVII. DEVELOPMENT OF THE BLADDERS. 425 sin1 ple elongated cells, runs up the short foots talk and divides at the base of the bladder. One branch extends up the middle of the dorsal surface, and the other up the middle of the ventral surface. In full-grown bladders the ventral bundle divid.es close beneath the collar, and the two branches run on each side to near where the corners of the valve unite with the collar; but those branches could not be seen in very young bladders. ~he accompanying figure (fig. 23) shows a section, which happened to be strictly medial, through the footstalk and between the nascent antennre of a bladder of Utricularia vulgaris, - 1- inch I 0 0 in diameter. The specimen was soft, and the young valve became separated from the collar to a greater degree than is natural, and is thus represented. We here clearly see that the valve and collar are infolded prolongations of the walls of the bladder. Even at this early age, glands could be detected on the valve. The state of the qU:adri:fid processes will presently be described. The antennre at this Frc. 23. ( Ftricula1·ia vulga1·is.) Longitudinal section through a young bladder, rlm of an inch in length, with the orifice too widely open. ~eriod consist of minute cellular projections (not shown 1n the above figure, as they do not lie in the medial plane), which soon bear incipient bristles. In five instances the young antennre were not of quite equal len?t~; and this fact is intelligible if I am right in behev1ng that they represent two divisions of the leaf, rising from the end of the bladder; for, with the true leaves, whilst very young, the divisions are never, as far as I have seen, strictly opposite; they |