ANIMAL PARASITES. 121 



cause considerable itching and pain, and in the eye- 

 hds inflammation and swelling. The parasite is indig- 

 enous to the western coast of Africa, and is of common 

 occurrence among the natives. 



Both Americans and Europeans (chiefly missionaries) 

 have harbored filaria loa after a residence in Africa, 

 and had them removed on returning to their respective 

 countries. Ward records the history of seven such 

 cases observed by physicians in various parts of the 

 United States, and has studied the specimens in a few 

 of them. He concurs with Manson in the opinion that 

 this filaria is a more mature form of the Filaria diuma.^ 

 Removal of the parasite is accomplished by grasping 

 the worm firmly through the cuticle with forceps, and 

 cutting down upon it with scissors or knife. Care 

 should be taken that the skinhold on the worm is not 

 loosened until the worm itself is grasped, or it may 

 escape into the deeper tissues. The embryos of the 

 worm are believed to be inoculated into man by an 

 intermediate host, either a fly or mosquito. Prophy- 

 laxis in filaria loa is the same as for malaria. 



The trichocephalus dispar (whip-worm) is 

 Trichiuris a common parasite of the intestinal tract, 

 Trichiura. particularly the caecum. Universally dis- 

 tributed, it apparently does little or no 

 harm, although anaemia and diarrhoea have occasionally 

 been ascribed to its presence. Both the worm and its 



* See Bui. Univ. of Neb., January, 1906. 



