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- 
Fic. 594.— Larve of the Horse 
Bot-fly. Slightly enlarged. 
Original. 
Fic. 595.—Eggs of the Horse Bot-fly, 
attached to hairs. 
ural size. 
371 
Original. 
Enlarged and nat- 
