254 SPHEGIB^. 



struggling with a huge cockroach ; the latter was either paralyzed 

 by a sting or dazed with fear, and was beiug half dragged by an 

 antenna and fore leg, half hustled and pushed along by the active 

 little wasp. 



Key to the Species. 



A. Fore wing with three cubital cells A. compressa, p. 254. 



B. Fore wing- with two cubital cells. 



a. Abdomen with the basal segment narrowed 



into a petiole. 

 «'. Petiole linear at base, nodose at apex. . A. constancere, p. 255. 

 h' . Petiole gradually widened to the apex, 



not nodose A. ruficornis, p. 255. 



b. Abdomen with the basal segment pseudo- 



sessile. 

 «'. Kaised central portion of the pronotum 

 not elevated at back into a tubercle. 

 or. Raised central portion of pronotum 



transversely striate A. novarce, p. 256. 



b'^. Raised central portion of pronotum 

 punctured. 

 a^. Raised central portion of pronotum 

 nearly cubical, as long as it is 



broad' A. latifrons, p. 256. 



h^. Raised central portion of pronotum 



much broader than long A. cognata, p. 257. 



b'. Raised central portion of the pronotum 

 elevated posteriorly into a cone or 

 blunt tubercle. 

 a^. Cheeks well developed, with a blunt 



rounded projection posteriorly .... A. sikkimensis, p. 257. 

 b^. Cheeks scarcely at all developed, 

 straight, with no rounded projection 

 posteriorly A. crudelis, p. 258. 



473. Ampulex compressa. 



Sphex compressa, Fabr. Ent. Syst. ii, p. 206. 

 Chlorion compressum, Fabr. Syst. Piez. p. 219. 

 Ampulex compressa, Jurine, Hym. p. 134. 



2 . Head in front coarsely and strongly punctured ; pronotum 

 tuberculate at back, the raised portion transversely striate, with a 

 short medial longitudinally-impressed line ; mesonotnm with one or 

 two coarse punctures, the sides of the thorax more finely and 

 closely punctured; median segment narrowed posteriorly and 

 truncate, a medial short longitudinal carina from base, one each 

 side of this slightly convergent posteriorly, another outer one on 

 each side forming at apex a continuous loop along the edge of 

 the truncation, a slight indistinct one outside again, and a fourth 

 lateral carina on each side ending in a sharp upturned tubercle 

 at each lateral posterior angle of the segment, the space between 

 the carinas transversely striate; legs stout, posterior tibias sparsely 

 punctate ; abdomen short, broad, the 2nd segment somewhat longer 

 than broad. Brilliant metallic blue, sometimes green, the inter- 



