47 6 



THE ANIMAL PARASITES OF MAN 



represent the long-known villous tufts, placed on disc-like cushions. In each of the 

 cylindrical villi which terminate blindly towards the body cavity there lies a 

 cilium, which springs from the membrane lining the villus, and which lies in a space 



cavity of the villus, which ultimately proceeds as a 

 little canal. There are three canals discharging into 

 the uterus that serve to conduct the excretory materials 

 from the body cavity ; special glandular cells corre- 

 sponding to the terminal cells of the Platyhelminths, 

 at the commencement of the system, are not present 

 in the Acanthocephala. 



\T. 



R.r. 



SEXUAL ORGANS. 



(a) Male Organs. The greatest part of the male 

 genital apparatus is contained in a muscular sheath 

 the ligament which originates at the posterior end 

 of the receptaculum proboscidis, passes along longi- 

 tudinally through the body cavity, and is inserted at 

 the posterior end of the worm. The two oval testicles 

 usually lie one behind the other ; their vasa efferentia 

 unite sooner or later into a vas deferens which passes 

 backwards, and finally terminates in the penis ; the 

 terminal portion of the conducting apparatus is sur- 

 rounded by six large glandular cells (prostatic glands) 



P. 



FIG. 348 A. The male o,f 

 Echinorhynchus augustatits. 

 L., lemnisci ; J*., testicles; *P., 

 prostatic glands ; P.r. t sheath of 

 proboscis, with ganglion ; R.r., 

 retractor of sheath of proboscis. 



FIG. 3486. Anterior portion of the female 

 apparatus of Echinorhyuchus acus. On the 

 left seen from behind, on the right seen from 

 the front. F, inferior orifice of the bell ; B, 

 bell; Z,ig, ligament; M, mouth of bell; Ut, 

 uterus. Magnified. (After Wagener.) 



the excretory ducts of which open into the vas deferens. The penis itself is placed 

 at the base of a bell-shaped invagination of the posterior end, the bursa, which is 

 everted during copulation. 



(6) Female Organs. There are only two ovaries present in the ligament during 

 the larval stage. During the course of growth they divide into accumulations of 

 ceHs (placentulse, loose or floating ovaries), which finally cause the ligament to burst 



