440 



THE ANIMAL PARASITES OF MAN 



15. Hypoderma bovis (De Geer), 1776. 



Ox hypoderma, ox gad fly, or warble fly. The female deposits her eggs 

 on the skin of cattle ; the young larvae bore deep into the subcutaneous 

 connective tissue, where they give rise to characteristic tumours, which may 

 attain the size of pigeons' eggs. When the larva has reached its full 

 size it again casts its skin and leaves its host to become a pupa on the 

 ground. The larva has also repeatedly settled in the skin of man (Spring, 

 Joseph, &C.). 1 



16. Hypoderma diana, Brauer, 1858. 



The larvae live in the skin of deer and roedeer ; they have also, in 

 three cases, been observed in man (Boithen, Joseph, Volkel.) 



FIG. 284. Larva of Der- 

 matobia cyaniventris in its 

 natural size and magnified. 

 (After Blanchard.) 



FIG. 285. Larva of Der- 



matobia cyaniventris, en- 

 larged. (After Blanchard. ) 



17. Gastrophilus, sp. 



The larvae of some species of Gastrophilus live in the stomach as well as in 

 the duodenum of horses. When they have become mature they leave the 

 intestine by the natural channel to become puparia in the ground. Cholod- 

 kowsky states that the " little worms " observed by Samson and Sokolew 



1 This species has frequently been confused with H. lineata, Villiers (vide Second 

 Rep. Sco. Zool. 1903.) F. V. T. 



