192 NATURAL HISTORY. 



datus) is ten lines long ; feet and abdomen yellow ; tail 

 and thorax black; latter spotted with yellow; selects 

 the larvee of the peacock's eye. 



The . Yellow Ichneumon (ophion luteus) is one inch 

 long, with compressed body, brilliant green eyes, and 

 short ovipositor : one yellow spot on the back. 



The Sickle Ichneumon (foenus jaculator) is eight 

 lines long, black; in the middle foxy, with two silver- 

 white spots on the head, and in flying elevate their 

 sickle-shaped bodies above the level of their wings. 



INSECTS OF THE FLY KIXD (Diptera) 



Have only two wings ; are without mandibles, but instead 

 are provided with a sucker, which, in some, have the 

 form, and serve as a sting. 



The Horse Bat Fly (oestrus equi) belongs to this 

 family, and in form resembles the large Muck Fly, but 

 in color a drone bee ; are found everywhere in the neigh- 

 borhood of horses. They lay their eggs in the inner part 

 of the fore legs ; the .animal, feeling the sting, licks the 

 spot; the nits, adhering to the tongue, are swallowed, 

 and, changed into larvae, fasten on the walls of the stom- 

 ach, and subsist on its secretions until fully grown, and 

 ready to assume the pupa state, when they are thrown 

 off, and receive their winged form in the open air. 



The Gad Fly (oestrus bovus) makes small punctures 

 in the backs of cattle, and deposits its eggs within the 

 wound. These soon become tumid, and, filled with pur- 

 ulent matter, on which these larva? live until ready for 

 the pupa state, when they crawl forth, and burying 

 themselves in the ground, await their transformation. 



The Sheep Bot (oestrus ovis) places its eggs in the 



