178 ENTOZOA. 



the latter lias one or two pores differently situated, according to the species, 

 which appear to be the orifices of ovaries that arc placed in the thickness of the 

 joints, where they are sometimes simple, and at others ramous. The Tienife 

 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 the four suckers. Such in Man 

 is the 



T. lata, Hud.; T. vulgaris, Gm.; Gcetz., XLI, 59. (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. soliunt, Lin.; Goetz., XXI, 1 7; Encyc, XL, 1522, and XLI, 17; 

 Ver solitaire of the French. Its joints, the anterior 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 some- 

 times met with. The vulgar idea that but one of these animals is found at a 

 time in the same individual is very far from being true. Its detached joints 

 are styled cucurbitini. It is one of the most dangerous of the intestinal worms 

 and the most difficult to expel. 



From these ordinary Teenize, on account of the form of their head, are 

 distinguished the 



TRICUSPIDARJA, Rudolphi, 



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. 



TENTACULARIA, Bosc., 



Only differ in consequence of the tentacula being unarmed. 



Naturalists have also distinguished from the ordinary Ta?ni(p those, which, 

 with a similar head, that is one with four suckers, have the body terminated 

 posteriorly by a bladder. Their joints are not as distinctly marked as in the 

 preceding ones. The genus 



CYSTJCERCUS, Rudolphi, 



Vulgarly termed Hydatids, is composed of those in which the bladder supports 

 but a single body and one head. They are particularly developed in the 

 membranes and cellulosity of animals. 



SCOLEX, Muller, 



Where the body is round, pointed behind, extremely contractile, and 

 terminated before by a sort of variable head, round which are two or four 



