ABT. 15. REVISION OF ICHNEUMON-FLIES MUESEBECK. 13 



ing the stigma; second cubital cell bordering the first discoidal at 

 base ; posterior coxae small ; spurs of posterior tibiae short ; abdomen 

 sessile, strongly depressed ; the first tergite extending at least half the 

 length of the abdomen. 



KEY TO THE NOKTH AMERICAN SPECIES OF ADELIUS. 



1. Anterior wings with two broad fuscous bands, one just before and- another 



just beyond the middle 2. 



Anterior wings, entirely hyaline; head, mesonotum and mesopleurae testa- 

 ceous, the mesopectus black 1. nigripectus, new species. 



2. Head entirely, and thorax except metanotum and propodeum, ferruginous; 



the fuscous bands on wings dark and well-marked ; head and mesonotum 



granular 2, fasciipennis (Rohwer). 



Head above and behind, and the thorax entirely, piceous to black ; the fuscous 

 bands on wings weak and poorly defined ; head and mesonotum punctate. 



3. coloradensis, new species. 



1. ADELIUS NIGRIPECTUS. new series. 



Somewhat resembles fasciipennis^ but is at once separated by the 

 clear hyaline wings, darker abdomen and receding temples. 



MaU. — Length 1.4 mm. Face twice as broad as long; vertex 

 rather long, flat, indistinctly punctate, shining; temples receding 

 sharply behind the eyes, and like the vertex, mostly smooth and 

 shining ; antennae nearly as long as the body ; mesoscutum distinctly 

 punctate anteriorly, impunctate and indistinctly alutaceous on pos- 

 terior half; scutellum fiat, impunctate; mesopleurae entirely pol- 

 ished with a longitudinal crenulate furrow below; propodeum im- 

 punctate and strongly shining, the dorsal aspect with a polished 

 median longitudinal furrow bounded by sharp carinae, and with two 

 distinct lateral carinae; a prominent transverse carina separating 

 the dorsal and posterior aspects of propodeum; metapleurae pol- 

 ished; stigma large, evenly rounded behind, the radius originating 

 far out and very short; the metacarpus less than one-third as long 

 as the stigma measured along anterior margin; legs rather stout; 

 posterior coxae about as long as propodeum, polished; posterior 

 tibiae very slender at base, thickening strongly toward apex; spurs 

 of posterior tibiae a little less than half as long as the metatarsus ; 

 abdomen very strongly depressed and entirely smooth and polished ; 

 first segment longer than the remainder of the abdomen. Head, 

 except the stemmaticum, which is black, bright testaceous; antennao 

 yellow on the basal third, fuscous beyond; mesoscutum, disk of 

 scutellum and pleurae ferruginous; mesopectus, lateral faces of 

 scutellum, metanotum and propodeum black; tegulae pale; wings 

 clear hyaline; legs including all coxae yellow, except the posterior 

 femora above, and their tibiae and tarsi, which are very slightly in- 

 fuscated. 



