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Show 368 ENTOZOA. DEROSTOMA· . . d th but nearer to the anterior ex- Where the oral orlfice lS un ernea tremity. . te the PB.IENIOURUS, Rud., or It is to the first that 1 approxl~\ t one orifice at the anterior VERTUMNUS, Otto, in which there lS u extremity· . . known-v. thethidicola, Otto. A c. Nat. But one specleS 1~ r f 2-a parasite of the Thethys jim- C~r., .x~, partblll,dp. : ~;eq. uently has a forked tail so shap~d bna; lt lS mar e ' an by being torn(l). FAMILY III. T J.ENIOIDEA. I th. d f:amily of parenchymatous Intestinal Worms, n our Ir . "d d · h we place all those species in which the head IS pro:I ~ ~It two or four suckers placed around its middle, whi?h IS I~elf to arked with a pore, arid sometimes furmshed Wlth ~~~~m . S . a little proboscis, naked or armed with spmes. ometlmes there are four little trunks thus armed. The most numerous genus is T&NIA, Lin. Th b dy of the Tape-worm is often excessively elongated, flat, com· poseed oof joints more or less distinctly marked, and narrowed ant~~ riorly, where we generally find a square head hollowed by four sma suckers. 1 b" h Observers have thought that they could perceive cana s w lC (1) For its anatomy, see Delle Chiaie, Memor., I, pl. ii, f. 9, 5. , PARENCIIYMATA. 369 arose from these suckers, and crept along the margin of the joints of the body. Each of the latter has one or two pores differently situated, according to the species, which appear to be the orifices of ovaries that are placed in the thickness of the joints, where they are sometimes simple, and at others ramous. The Trenire are among the most cruel enemies of the animals in which they are developed, and which are apparently exhausted by them. In some, there is no projecting part in th'e four suckers. Such in Man is the T. lata, Rud.; T. vulgaris, Gm.; Gretz., XLI, 5-9. (The Common Tape·worm.) The joints are broad, short, and furnished with a double pore in the middle of each side. It is very frequently twenty feet in length, and it has been found upwards of a hundred. The large ones are nearly an inch wide, but the head and anterior portion of the body are always very slender. This species is extremely injurious and tenacious. The most violent remedies frequently fail to expel it. In others, the prominence between the suckers is armed with little radiating points. Such is the T. solium, L.; Gretz., XXI, 1-7; Encyc., XL, 15-22, and XLI, 1-7; 1ler solitaire of the French. Its joints, the ante· rior ones excepted, are longer than they are wide, and have the pore placed alternately on one of their edges. It is usually from four to ten feet in length, but much larger ones are sometimes met with. The vulgar idea that but one of these auimals is found at a time in the same individual is very far from being true. Its detat1ted joints are styled cucurbitini. It is one of the most dangerous of the intestinal worms and the m'ost diffi-cult to expel( 1 ). • From these ordinary Trenire, on account of the form of their head, are distinguished the TRICUSPIDARIA, Rud. Now called Trianophora by the same author, where the head divided as it were into two lips or lobes, instead of suckers has ,two tri-pointed spinuli or stings, on each side. ' (1) For the other species, sec Rud., Hist., II, 77, and Syn., 144. VoL. IV.-2 W |