GENERAL ZOOLOGY 



Spines 



Anterior 

 ganglion 



Ejaculatory 

 duct 



Excretory ( 



pore ^~ 



Nerve 

 trunk 



.'■<? 







Rosette ( ]<^^P'^^' 





Acetabulum 



Vagina 

 Testis 



Uterine sac 



Seininal 

 receptacle 



Posterior 

 ganglion 



Fig. 11.16. A typical cestodarian, Gyrocolyle ftmbnalo, from the intestine of the ratfish. 

 (Reproduced from J. E. Lynch, 1945, Journal of Parasitology, vol. 31, printed by permission.) 



intestinal parasites in vertebrate hosts, and their larval stages are parasites 

 in the bodies of animals upon which the final host feeds, or which are likely 

 to be ingested by the final host with its food. The intermediate host is in- 

 fected by eggs and embryos from the feces of the final host. 



The structure and life cycle of the pork tapeworm, Taenia solium, which 

 infests man, is representative of a large order of tapeworms. Infestation by 

 this species is still common in countries where raw or imperfectly cooked pork 



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