16 PEOCEEDINGS OP THE NATIONAL MUSEUM vol.69 



Head transverse, but frequently swollen behind the eyes, at least 

 as broad as the thorax, and not distinctly rostriform; face much 

 broader than long from antennal foramina to apex of clypeus; malar 

 space usually half, or more than half, as long as the eye height; 

 clypeus large, broad, convex, often a Uttle elevated anteriorly; man- 

 dibles rather long, bidentate, the superior tooth long and acute, the 

 inferior tooth very short; palpi normal, the maxillary palpi 5-seg- 

 mented, the labial 4-segmented; frons smooth, the frontal impressions 

 not margined by carinae; ocelli small, ocell-ocular line always much 

 more than twice as long as the diameter of an ocellus; parapsidal 

 furrows impressed; mesopleural furrow usually foveolate; propodeum 

 sloping gradually from base to apex or slightly rounded, rugulose, 

 not areolated; legs moderate; posterior tibiae without short stout 

 spines outwardly at apex, above the outer terminal spur; inner spur 

 of hind tibiae varying from a Uttle shorter to much longer than 

 half the basitarsus; tarsal claws simple, never cleft, nor with a basal 

 tooth; wings dusky; radius arising at or beyond middle of stigma; 

 second cubital cell small, sub triangular, obhque, petiolate; first cubi- 

 tal and first discoidal cells confluent; abdomen very narrow at ex- 

 treme base, broad at the middle, completely poUshed, with not even 

 a suggestion of sculpture; first tergite rather flat, slightly impressed 

 at base, without dorsal longitudinal keels, narrow at base, strongly 

 widened to the apex, where it is at least nearly as broad as long; 

 hypopygium not prominent ; ovipositor extremely short, the sheaths 

 scarcely projecting beyond apex of abdomen. Head and thorax 

 varying from testaceous to black; abdomen always testaceous or 

 ferruginous, rarely black at extreme base. 



KET TO THE SPECIES OF CRASSOMICEODUS 



Crassomicrodusf melanopleurus (Ashmead) is not included in this 

 key. See page 22. 



1. Head and thorax entirely black; first abdominal tergite black basally; all 



coxae and trochanters black; parapsidal grooves sharply impressed and 

 finely foveolate; furrow in front of scutellum divided into 6 or more pits 



by distinct septa . 1. nigrithorax, new species. 



At least the mesonotum testaceous 2. 



2. Anterior wing hyaline at apex; propodeum straight, not rounded from base 



to apex; impression between lateral ocelli deep, weakly foveolate; inner 

 spur of hind tibia longer than half the basitarsus 



2. apicipennis, new species. 

 Anterior wing not hyaline at apex; propodeum usually distinctly a little 

 rounded from base to apex; impression between lateral ocelli usually shal- 

 low and smooth; length of inner spur of hind tibia variable 3. 



3. Inner spur of posterior tibia not distinctly longer than half the basitarsus; 



last segment of hind tarsi much longer than the third, and nearly or quite 

 as long as the second; cheeks and temples bulging prominently; cheeks, in 

 front view, strongly rounded 4. 



