362 Descriptions of British Diptera. 



The body is divided into twelve rings, the anal one being very 

 minute and resembling a tubercle, (Fig. 1.) The head is pro- 

 vided with two short antennae and several minute organs, among 

 which the most conspicuous are two scaly hooks, which it employs 

 in opening a passage for itself in the earth, and in aiding its mo- 

 tions. The latter, however, are chiefly accomplished by means of 

 numerous retractile tubercles placed on a dark-coloured band 

 encircling most of the segments, which, by their pressure against 

 the plane of position, preserve the space gained by the elongation 

 of the rings. With the exception of the bands just mentioned, the 

 colour is dirty white, the head brown and shining. The pupa is 

 nearly cylindrical, of a greyish-brown colour, the segments fringed 

 on the posterior margins with grey hairs (Fig. 2.) The anal seg- 

 ment is small, and armed with six sharp scaly points, (Fig. 3.) 

 which seem to enable the pupa to push its head above the surface 

 of the soil, as it is always observed to do, while the lower portion 

 remains imbedded.* 



The species of this genus hitherto recorded as British, form but 

 a small proportion of such as are known to inhabit corresponding 

 latitudes on the continent, and it may therefore be expected that 

 considerable additions will yet be made to them. Meigen de- 

 scribes forty-two. 



Tabanus bovinus. (s.) 

 Tab. bovinus, Linn. De Geer, vi. 219. pi. 12, fig. 10 and 11 ; Fabr. 

 Meigen. ii. p. 43. Wood's Illus. pi. 60. 

 Ground colour brownish-black ; eyes brassy-green during life ; 

 antennae blackish at the tip, and inclining to ferruginous at the 

 base ; hypostome, forehead, and all the oral organs, except the la- 

 bium, greyish-yellow : thorax with several depressions on the sur- 

 face, clothed with yellowish-grey hairs, and having indistinct dark- 

 coloured longitudinal stripes : scutellum and abdomen of the same 

 colour as the thorax : hinder edge of the abdominal segments 

 with a reddish-yellow band, variable in breadth, and a whitish tri- 

 angular spot in the middle of each : under side covered with cinere- 

 ous pubescence inclining to yellow, each abdominal segment with 

 a rather large semicircular black spot in the centre, and a narrow 

 oblique black line on each side of it : thighs and tarsi blackish : 

 tibiae yellowish- white, more or less dusky at the apex : wings brown- 

 ish, the costal and discoidal nervures yellowish-brown ; winglets 

 and halteres brown. Length 10— 12^, breadth 4— 4§ lines. 



* De Geer, Vol. vi. 214- 

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