THE INSECTS OF NEW JERSEY. 



773 



Family GESTRID^. 



These are the "bot-flies," usually of good size, sometimes very large, 

 and peculiar by having the mouth parts almost entirely aborted. Some 

 are hairy, yellow, with rather a pointed abdomen; others are very plump, 

 blue black, with a white bloom, and very formidable in appearance. The 

 larvae live in the nasal passages, in the stomach or beneath the skin of 

 the animals infested by them, and often cause serious functional disturb- 

 ance. They also lessen the value of the skins. The ordinary bots attack- 

 ing horses and cattle lay their eggs on the hair of the animals, where 

 they are likely to be licked off, and so brought into the mucus-lined 

 passages; hence it is a good plan, where bots are numerous, to keep 

 horses cleaned and brushed and to prevent their licking themselves. 

 Bots beneath the skin should be treated with mercurial ointment, and 

 after a day or two squeezed out through a sufficient incision. Where they 

 infest the stomach, or get into the nasal passages, a veterinarian must be 

 consulted. 



GASTROPHILUS Leach. 



G. equi Fab. The horse bot-fly, which spends the larval stage in the in- 

 testines, and is passed naturally when full grown; it pupates under 

 ground and the eggs are laid on the hair. 



G. nasalis Linn. Caldwell (Cr). 



HYPODERMA Clark. 



The ox bot, Hypoderma lineata: a, eggs attached to hair; 

 b, fly; c, larva. 



Fig. 320. 



i 



H. lineata Villers. The "Ox Warble"; occurs rarely throughout the State. 

 H. bovis De Geer. Atlantic City, Belvidere (U S Ag). 

 These species live under the skin and form tumors and ulcers. 



