GASTEROPHILUS. 2?3 



" This is supposed to be one of the two species of gad-fly which 

 infest fallow-deer. One of these deposits its eggs in an orifice it 

 makes in the skin of the animal, and so produces tumours ; the 

 other lays its eggs in such a manner that its larvae, when hatched, 

 can make their way into the head, where they take their station 

 in a cavity near the pharynx. There are two fleshy bags as big 

 as a hen's egg, and of a similar shape, near the root of the tongue 

 of the deer; these are inhabited by the larvae in considerable 

 numbers, and between sixty and seventy bots have been taken 

 from one of them. The larvae have been found in England in 

 deer that had been killed for venison ; they were stationed in the 

 throat, just at the commencement of the oesophagus. They much 

 resemble the larvae of (Estrus Ovis, but are proportionately longer 

 and less angular." Very rare. (E.) 



Genus III. GASTEROPHILUS. 



GASTEROPHILUS, Lea. (Estrid. Ins. (1817); Zett. (Estrus p., L. ; 

 D. G.; F. ; Hbst. ; Schr. ; Gmel. ;. Clark ; Fal. ; Latr. ; Mcq. ; 

 Guer. ; Westw. Gastrus, Meig. 



Corpus sublineare, hirtum. Caput breve, thorace angustius. Frons 

 magna, antice latior. Fades parva, concava. Antennae brevissimae. 

 Ala medicares; vena costalis ala multo brevior; prabrachialis ad 

 marginem posticum terminata ; discalis transversa fere recta, subob- 

 liqua. Alula minima. Abdomen subtus recurvum, thorace longius. 

 Pedes mediocres ; ungues et onychia sat longa. 

 Body nearly linear, hairy. Head short, narrower than the thorax. 

 Interfrontalia large, triangular. Front broad, widening towards the 

 fore border, which is concave. Face small, concave. Genre large. 

 Eyes of moderate size, rather narrow, nearly elliptical. Antenna very 

 short, seated in the cavity of the face ; first and second joints very mi- 

 nute ; third round ; fourth and fifth obsolete ; sixth setiform, slender, 

 bare. Thorax not longer than broad, with a slight transverse furrow ; 

 scutellum small, nearly semicircular. Wings moderately long, slightly 

 rugulose ; costal vein ending at some distance in front of the tip of the 

 wing; subcostal ending at much before half the length; mediastinal 

 ending at before two-thirds of the length ; radial ending at about five- 

 sixths of the length ; cubital ending at the tip of the costal ; prcebra- 

 chial nearly straight, slightly inclined hindward, and ending on the hind 

 border at some distance from the tip; pobrachial and anal curved to- 

 wards the hind border ; discal transverse nearly straight, slightly ob- 

 lique, parted by nearly four times its length from the border. Alula 

 very small. Halteres uncovered. Abdomen as broad as the thorax, 



VOL. II. 2 N 



