42. 

 PACHYGASTER LEACHII. 



Order Diptcra. Fam. Stratiomydae Lat., Leach. 



Type of the Genus Vappo ater Fab. 



P.vcnYGASTER Meig. Vappo Lat., Fab. Nemotelus Pz. 



Antenncc approximating, porrected, hairy, 3-jointed, first joint 

 small, second large, transverse, third large, somewhat hemi- 

 spheric, compressed, having a reticulated appearance under a 

 lens, and 2 indistinct transverse rings (Meigen says 4) with a 

 hairy seta attached to the outer side near the extremity. (3.) 

 Labrum horny, robust, cylindrlc, grooved beneath, dilated at 

 the base, obtuse and notched at the apex. (1. b.) 

 Tongue horny, acute, attenuated from the base, shorter than the 

 labrum. (c.) 

 Mandibles none. 



Maxillce long, slender, acute, concealed in the lip. (e.) 

 Palpi 2, oblong, cylindric, very minute, slightly pilose, attached 

 to the base of the niaxilhe. (f.) 

 Menfum large, cylindric, inclining upward, (h.) 

 Lip fleshy, large, oval, bipartite, pilose, (g.) 

 Proboscis shorter than the head, concealed when at rest. Eyes approxi- 

 mating above in the males. Ocelli 2i , placed, anteriorly in themales, 

 posteriorly in the females. Thorax obovate, with a transverse suture. 

 Scutellum without spines. Abdomen large, nearly globular, being 

 convex above, composed of 5 obscure segments. Legs simple. Tarsi 

 h-jointed, with 2 claws and pulvilli (8. a fore leg.) Wings incum- 

 bent, when at rest placed parallel upon the abdomen, long, lanceolate, 

 nerves very faint, Halteres large, ovate. 



Leaciiii Stephens' MSS. 



Black, shining, punctured. Antennae orange, eyes purplish or 

 slightly red, legs pale straw colour, the posterior thighs with a 

 black spot near the apex. Halteres fuscous. Wings entirely 

 transparent, iridescent, nerves very pale brown. 



In the Cabinets of the British Museum and the Author. 



Paciiygaster atcr is the only insect of this Genus hitlierto 

 described ; it is figured by Panzer, is somewhat larger than our 

 insect, and is at once distinguished by its wings, which are 

 brown nearly halfway from the base. P. LcacJiii ajipears to be 

 very rare, the only specimens discovered, being a male in the 



