INSECTS AFFECTING MAN AND ANIMALS 



195 



entirely impracticable for cattle in a large pasture. The 

 best means of control is to examine the cattle carefully in 

 the winter and spring and to remove the maggots from be- 

 neath the skin as soon as they are in evidence. This can 

 be done by exerting a gentle pressure with the fingers on 

 either side of the hole and thus squeezing the maggot out. 

 A cheap pair of tweezers will aid in removing the younger 





FIG. 138. Ox warble (Hypoderma lineata). (From "Insect Life.") 



a, second stage of larva from back; b and c, enlargement of extremities; d, 

 ventral view of third stage with details of extremities at e and /; g, dorsal view of 

 mature larva with enlargement of anal spiracles at h; i, the same, lateral view; 

 natural size indicated by side lines. 



ones. Inject a few drops of cresol or carbolic solution in 

 the wound after removing the maggot. It is sometimes 

 recommended to kill the maggots by applying grease and 

 other substances which will stop up the breathing hole and 

 kill them beneath the hide, but this is liable to cause festering. 



120. The Horn Fly.* The little horn flies (23), which 

 cluster upon the horns of cattle, are among their most 



* Hcematobia serrata Rob.-Desv. Family Muscidce. See page 141. 



