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Show 410 UTRICULARIA NEGLECTA. CHAP. XVII. a llo w animals to enter and to prevent their esc· ape1; - and as the inside of the bladder presents so ~Ingu ar a structure, clothed with innumerable quadnfid and bifid processes, it is impossible to dou~t that the plant has been specially adapted for secu~Ing prey. From the analogy of Pinguicula, belonging to the same family, I naturally expected tha.t ~he l>ladders would have digested their prey; but this IS n?t the case, and there are no glands :fitted for secreting .the proper fluid. Nevertheless, in order to test theu power of digestion, minute fragments of roas~ meat; three s1nall cubes of albumen, and three of cartilage, were pushed through the orifice into the bladders of vigorous plants. They were left from one day to three days d half within and the bladders were then cut aonp ena; but none of ' the abo.ve sub.stances exh I'b 'I te d t h e least siO'nS of digestion or dissolution; the angles of the 0 b . cubes being as sharp as ever. These o se:vations were made su bseq uen tl y to those on Drosera, Dion~a? Dro~ophyllum, and Pinguicula; so that I was familiar with the appearance of these substances when undergoing the early and final stages of digestion .. we may therefore conclude that Utricularia cannot digest the ani1nals which it habitually captures. In most of the bladders the ca pturod animals are so much decayed that they form a pale brown, pulpy mass, with their chitinous coats so tender that they fall to pieces with the greatest ease. The black pigment of the eye-spots is preserved better than a~ything else. Li1nbs, jaws, &c .. are often found qui~e ·detached· and this I suppose IS the result of the vain struggles' of the later captured animals. I. have. sometimes felt surprised at the sinall proportion. of imprisoned animals in a fresh state comp.ared With those utterly decayed. Mrs. Treat states w1th respt~ct CHAP. XVII. ABSORPTION BY THE QUADRIFIDS. 411 to the larvce above referred to, that "usually in less "than two days after a large one was captured the fluid "contents_ of the bladders began to assume a eloudy "or muddy appearance, and often became so dense " that the outline of the animal was lost to view." This statement raises the suspicion that the bladders secrete some ferment hastening the process of decay. There is no inherent improbability in this suppositio~, considering that meat soaked for ten minutes in water mingled with the milky juice of the papaw becomes quite tender and soon passes, as Browne remarks in his 'Natural History of Jamaica,' into a state of putridity. Whether or not the decay of the imprisoned animals is in any way hastened, it is certain that matter is absorbed from them by the quadrifid and bifid processes. The extremely delicate nature of the membrane of which these processes are formed, and the large surface which they expose, owing to their number crowded over the whole interior of the bladder, are circumstances all favouring the process of absorption. Many perfectly clean bladders which had never caught any prey were opened, and nothing could be distinguished with a No. 8 object-glass of Hartnack within the delicate, structureless protoplas1nic lining of the arms, excepting in each a single yellowish particle or modified nucleus. Sometimes two or even three such particles were present; but in this case traces of decaying matter could generally be detected. On the other hand, in bladders containing either one large or several small decayed animals, the processes presented a widely different appearance. Six such bladders were carefully examined; one contained an elongated, coiledup larva; another a single large entomostracan crustacean, and the others from two to five smaller ones, all |