ANIMAL PARASITES. 119 



vessels of the trunk. The mature parasites measure 

 from S;^ milhmeters (male) to 155 millimeters (female) 

 long, by 5 millimeters broad; the embryos are about 

 the diameter of a red blood-corpuscle in thickness and 

 about 30 times as long. This filarium is widely dis- 

 tributed, being found in the Southern United States, 

 South America, India, China, Japan, West Indian 

 Islands, etc. 



The most important lesions resulting from the para- 



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Fig. 7. — Larval filaria hancrofti in blood. (Coplin.) 



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Site and its embryos are those due to obstruction of 

 important lymph channels, which leads to a hyper- 

 plastic condition of the tissues of the parts affected. 

 On account of the huge enlargement of the parts, and 

 their peculiar varicose appearance, the disease is called 

 elephantiasis. The disease is never general, affecting 

 only either one or both legs, the scrotum (lymph scro- 

 tum), one or both labia, or a breast, etc. 



