138 INFECTIOUS AND PARASITIC DISEASES. 



or more in length. The head is narrow transversely 

 (0.71 millimeters) and differs from the tcenia in having 

 two lateral grooves or bothridia as suckers. There 

 are no booklets. 



Fish act as intermediate hosts for the measles, stur- 

 geon, pike, perch, etc. In the stools of a person harbor- 

 ing the bothriocephalus, eggs characteristic of the worm 

 are found in large numbers. These find their way 

 into water, when the embryos escape 

 from the eggs and lead a free existence for 

 an unknown period. They are finally 

 swallowed by their fish-hosts, from whom 

 man in turn acquires the adult worm. 



This is a dog tape- worm 

 which is widely distributed. 

 Its intermediate hosts are the 

 dog-louse and flea, and the 

 ordinary flea of man {pulex n^^^m 



Depylidium 

 Caninum 

 (taenia cu- 

 cumerina). 



Fig. 16 



Dipy- 

 caninum. 



irritans). Its chief interest (Leuckart after 



. , 1 1 • -, 1 M 1 Weinland.) 



m human pathology is that children occa.- 



sionally harbor the adult worm, contracting it from 



the dog's louse or flea. 



Known also as the '^ dwarf-tape- worm," 

 Hymeno- is a short cestode parasitic in rats, 

 LEPsis Nana, mice, and man. The intermediate host 



is not known. The worm is known 

 throughout Europe, and lately many cases have been 

 reported from the Southern United States (Stiles). 



