STEONGYLID^ OE PALISADJS-WOEMS. 



65 



Sclerostomes have a similar life-history. They do not enter the 

 blood as does S. armaium. The eggs are introduced in water, 



Fig. 22.— Sci-ekostomum tetracanthhm. 

 Male (six times nat. size), and enlarged anterior extremity. 



and probably forage, and give rise to embryos which encyst 

 direct in the walls of the csecum and colon, where they form 



Fig. 23. — Small Bed Sclkrostome (S. ruhrum) from HoRsii; (female). 



tumourous patches similar to S. equinum. Here lying in the 

 cysts the white coiled worms (fig. 17) produce inflammation, 

 colics, and serious anasmia. When mature they make their 



