OCR Text |
Show 362 ENTOZOA. form of a proboscis armed with little hooks bent posteriorly, and susceptible of being retracted or protruded by the action of particular muscles. At its extremity we sometimes observe a papilla or pore which may be an organ of absorption, but it is certain that if the animal be plunged into water it becomes universally distendetl, and absorbs that liquid through the whole surface, on which it is thought we can discover a network of absorben.t vessels. No other parts that can be compared to i-ntestines are visible internally, than two slightly elongated creca attached to the base of the tubiform prominence; a vessel extends throughout its length on each side. A thread that runs along the inferior face of the animal is considered by M. de Blainville as its nervous system; but neither Rudolphi nor Cloquet coincide with him. Certain species have a distinct oviduct; in others the ova are disseminated throughout the cellulosity or parenchyma of the body. The males are provided with a little bladder at the end of the tail, and very distinct internal vesicula: seminales. We may believe that they fecundate the ova after they are ex.truded. These worms cling to the intestines by means of their proboscis, and frequently penetrate through them, so that individuals are some· times found in the thickness of their tunics, and even in the abdo· men, adhering to their external parietes. E. gigas, Gm.; Gretz., X, 1-6; Encyc. XXXVII, 2-7. The largest species known; it inhabits the intestines of the Hog and Wild Boar, where the females attain a length of fifteen inches(l). Certain species, in addition to the prickles on their proboscis, are armed with them in some other part of the body. HJERUoA, Gm. Only differing from Echinorhynchus in the prominence, which is reduced to a single crown of spines, terminated by double hooks. H. muris, Gm.; Echinorhynchus hreruca, Rud.; Gretz., IX, B., 12; Encyc., Vers, XXXVII, 1(2). It inhabits the liver of Rats. ( 1) For the other species, see Ru~, Hist. II, 251, and Syn., p. 63. (2) Id., lb., 292, etseq. PARENCHYMATA. 363 FAMILY II. TRE.l\fADOTEA, Rud. Our second family comprjses h . derneath the body or at 1 ·ts t t o~e which are furnished un- . ' ex rem1ty w·th cuppmg-glasses, by which the dh ' I org~ns resembling They may all be united . y a ere to the VIscera. In one genus, or the , FAsCIOLA, Lin. Which may be subdivided in the foll . number and position of the· owmg manner, according to the lr organs of adhesion. FESTUOARIA ' s Ch r.-M ONOSTOMA, Zed. Where there is but one of th extremity and sometimes d ose organs, sometimes at the anterior B. un erneath the 5 d ous 1rds and Fishes( 1 ). arne en · Found in vari- STRIGEA' Ab1 'l d .-A MPHISTOMA, Rud. Where there is a cup at each extremit . rupeds, Birds, &c.( 2 ) Y· Found m various Quad- T o t hl'S subgenus we must probabl Y approxi. mate the of(~ Rud., Hi.st., II, p. 325, and Syn. 82; the HYP V e same, With a depressed body and 1 OBTOMA, Blainv., are a division B a~ Hasselt and Kuhl have disco:ered ~ups p aced un~er the anterior extremity. ~2 et. of Fer.uss., 1824, vol. II, P· 311. wo new species in the Chelonia midas, ) Rud._, Hlst., P· 340, and Syn., p. 87. . |