FLATWORMS 



is eaten. The structure is similar to that of Taenia mginata, the beef tape- 

 worm, and that of Taenia pisiformis, which is common in dogs wherever dogs 

 prey upon wild rabbits. The scolex in this genus bears four suckers and 

 is surmounted by a crown of hooks, the so-called rostellum. Behind the 

 scolex is a budding zone where the proglottids originate. As new ones are 

 formed, the older ones become farther removed from the scolex and finally 

 detach, either singly or in short chains, from the free end of the worm, to pass 

 out of the host with its feces. 



Fig. 11.17. Adult taenioid tapeworm. (Redrawn from K. von Frisch, 1953, Biologie, vol. 2, 

 by permission of Bayerischer Schulbuch-Verlag.) 



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