164 



COLLEGE ZOOLOGY 



ne.ru. 1 



the liver-fluke, 

 but not so well 



<***** its parasitic 

 habits. There 

 is no alimentary 

 canal, the di- 

 gested food of 

 the host be- 

 ing absorbed 

 through the 

 body-wall. The 

 nervous system is 



FIG. 108.-- A proglottis of the tapeworm, Tauiia solium, similar to that 

 with mature reproductive apparatus, can.excret, longi- r pj n ,, nr : n anr J 

 tudinal excretory canals with transverse connecting 

 vessels; gl.vit, vitelline or yolk-glands; nrrv.l, longi- 

 tudinal nerves; ov, ov, ovaries; par. gen, genital pore; 

 schld, shell-glands; uler, uterus; vag, vagina; vas.def, vas 

 deferens. The numerous, small, round bodies are the developed (Fig. 

 lobes of the testes. (From Parker and Haswell, after T0 o n 



Leuckart.) 100, HC)l. L). 



Longitudinal ex- 

 cretory tubes, with branches ending in flame-cells, open at the 

 posterior end and carry waste matter out of the body (Fig. 108, 

 can. excret.). 



A mature proglottid is almost completely filled with reproduc- 

 tive organs ; these 

 are shown in 

 Figure .108. Sper- 

 matozoa originate 

 in the spherical 

 testes, which are 

 scattered about 

 through the pro- 

 glottis; they are 

 collected by fine 

 tubes and carried 

 to the genital pore 



rl 



FIG. 109. Stages in the development of the tape- 

 worm, T&nia solium, to the cysticercus stage, a, egg 

 with embryo, b, free embryo, c, rudiment of trie 

 head as a hollow papilla on wall of vesicle, d, bladder- 



(por.gen ) bv way worm ( c y st i cercus ) with retracted head, e, the same 

 y with protruded head. (From Sedgwick, partly after 

 of the vas deferens Leuckart.) 



