CHAPTER XXV 



Insect Pests of Domestic Animals 



Many different species of insects live as parasites on or in domestic 

 animals. Some of these have totally different habits and character- 

 istics; and thus the treatment for one will not always answer for 

 another. But between many species only minor differences exist. 

 The commoner and more typical forms will be given here. 



The Horse Bot-fly (Gastrophilus equi Fab.) 



In its larval stage this insect is an internal parasite within the 

 stomach of the horse, where it lives attached to the walls. It injures 

 the animal by interfering 

 with digestion and by the 

 irritation set up by its pres- 

 ence. 



The adult fly frequents 

 horses throughout midsum- 



FiG. 594. — Larvae of the Horse 

 Bot-fly. Slightly enlarged. 

 Original. 



Fig. 595. — Eggs of the Horse Bot-fly, 

 attached to hairs. Enlarged and nat- 

 ural size. Original. 



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