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Show 416 UTRICULARIA NEGLECTA. CHAP. XVII. vVe have seen with Drosera that the first effect of a weak solution of carbonate of ammonia on the cellcontents is the production of the finest granules, which afterwards aggregate into larger, more or less rounded, masses; and that the granules in the layer of protoplasm which flows round the walls ultiinately coalesce with these masses. Changes of this nature are, however, far Inore rapid in Drosera than in Utricularia. Since the bladders have no power of digesting albumen, cartilage~ or roctst meat, I was surpr.ised that. mat.ter was absorbed, at least in one case, from a fresh Infusion of raw meat. I was also surprised, from what we shall presently see with respect to the glands round the orifice, that a fresh solution of urea produced only a 1noderate effect on the quadrifids. As the q uadrifids are developed from pa pillre which at first closely resemble those on the outside of the bladders and on the surfaces of the leaves, I may here state that the two hemispherical cells with which these latter papillre are crowned, and which in their natural state are perfectly transparent, likewise absorb carbonate and nitrate of ammonia; for, after an immersion of 23 hrs. in solutions of one part of both these salts to 437 of water, their primordial utricles were a little shrunk and of a pale brown tint, and sometimes finely granular. The saine result followed from the immersion of a whole branch for nearly three days in a solution of one part of the carbonate to 1750 of water. The grains of chlorophyll, also, in the cells of the leaves on this branch became in many places aggregated in to little green masses, which were often connected together by the finest threads. On the · Absm~ption of certain Flu.ids by the Glands on the Valve and Collar.-The glands round the orifices of bladders which are still young, or which have been CHAP. XVII. ABSORPTION BY THE GLANDS. 417 long ke~t in. mode.rately pure water, are colourless. and then pnmordial utricles are only sli htl o;. hardly a. t all granular. But in the gr,e a t er nugm byer of. plants In a state of nature-and we mus t remem b r th. at they generall. y grow in very l.[' 'oul wa t er -anc1 With plants kept In an aquarium in .['oul t f l 1 ' wa er, most o t 1e glands were of a pale brownish tint. th ·. .· d . 1 . l , en pnm-or Ia u tnc . es were. more or less shr·unk , some tI' mes ruptured, with .t hen contents often coarsel y granu1 a r or aggrega~ed Into little masses. That this state of the glands Is. due t.o their having absorbed matter from t. he sudr'r ounding water, I cannot doubt· for as w h 11 1 , , e s a Im~e. Iate y ~ee, nearly the same results follow from · Nth eu .I mm. ersion for a few hours in various soltl tl'O llS. o~· Is It ~ro~able that this absorption is useless, ~eeing that It Is almost universal with plants growing In a state of nature, excepting when the water is remarkably pure. The pedicels of the glands which are situated close to the slit-like orifice, both those on the valve and on t~e collar, are short ; whereas the pedicels of the more distant glands are much elongated and project inwards. The glands are thus well placed so to be washed by a~y fluid coming out of the bladder through the onfice. T~e valve fits so closely, judging from the result of Immersing uninjured bladders in various solu.tions, that it is doubtful whether any putrid fluid habitually passes outwards. But we must remember that a bladder generally captures several animals· and that each time a fresh animal enters, a puff of foul water must pass out and bathe the glands. Moreover, I have r.epeatedl~ found that, by gently pressing bladders which contained air, minute bubbles were driven out t.hrough the orifice ; and if a bladder is laid on blotting paper and gently pressed, water oozes out. 2 E |