272 CESTRID^. 



oblique, parted by a little less than its length from the border, and by 

 a little more than its length from the pra^brachial transverse. Alulce 

 very large. Ilalteres concealed by the alulfe. Abdomen nearly oval, a 

 little narrower but not longer than the thorax ; dorsal segments extend- 

 ing beneath, where they are slightly retracted towards the base ; ventral 

 segments very small. Legs rather short and slender; vuigues and 

 onychia small. 



1. Ovis, L. Fn. 1734 (1761); F. ; Schr. ; Gmel. ; Lea.; Latr. ; 

 Clark ; Fal. ; Meig. ; Mcq. ; Zett. Fusca, n'ujro-tuherculata, capita 

 subtus antennisque testaceis, harum articulo tertio pectoreque nigris, 

 halteribus albidis, abdomine nigro argenteo-tessellato, pedibus fulvis. 

 Long. 5 ; alar. 10 lin. 



Head and thorax pale hrown above, xo'itli numerous minute blach tuber- 

 cles. Head testaceous in front and beneath. Antennae testaceous ; 

 third joint black above. Pectus black, clothed with pale hairs. Wings 

 quite limpid, rugulose ; veins testaceous. Halteres whitish. Abdomen 

 black or dark brown, tessellated with silvery-white tomentum. Legs 

 pale tawny. 



" Infests sheep, and lays its eggs on the inner margin of the 

 nostrils, from whence the maggots make their way into the head, 

 feeding in the maxillary and frontal sinuses on the mucilage there 

 produced. When full grown, they fall through the nostrils to 

 the ground, and. become puppe. Sometimes the maggots make 

 their way even into the brain, and occasion the death of the animal. 

 In order to prevent the gad-fly from getting at their nostrils, the 

 sheep shake their heads and strike the ground violently with their 

 fore feet ; or run away, and, getting into ruts, dry dusty spots, or 

 gravel-pits, crowd together and hold their noses close to the 

 ground. The anal plates are surmounted by a central boss, which 

 is a valve that closes the respiratory orifices." Generally distri- 

 buted. (E. S. I.) 



2. picta, Meg. ; Meig. Zw. iv. 172. 8 (1824); Curt.! B. E. iii. 

 106. Argenteo-c'merea, nigro-hirta, capite tessellato, fronte scutelloque 

 castaneis, facie antennisque ferrugineis, thorace abdomineque nigro- 

 variis, alls limpidis basi flavescentibus, pedibus ferrugineis, femoribus 

 nigro- variis. Long. 5 ; alar. 10 lin. 



Bodi/ grey, silvery, clothed with black hairs. Region of the ocelli and 

 hind part of the head tessellated with grey. Front castaneous, with 

 grey glance. Face pale ferruginous, with a hoary tinge. Eyes fer- 

 ruginous. Antennse pale ferruginous, with a hoary tinge. Thorax 

 adorned with black spots and stri])es. Scutellum castaneous. Wings 

 colourless, yellowish towards the base ; veins brown. Alulae brown. 

 Abdomen silvery, variegated with black. Legs ferruginous ; thighs 

 partly black and grey beneath. 



