ART. 21. NEW SPECIES OF ICHNEUMON-FLIES CUSHMAN. 13 



long as stigma, radius curving sharply forward at apex; inter- 

 cubitus much shorter than second abscissa of cubitus ; second recur- 

 rent nearly straight; nervulus postfurcal; nervellus broken at lower 

 two-fifths, inclivous; first tergite about half as wide at apex as 

 long, the spiracles subprominent ; gastrocoeli transverse, removed 

 from base of tergite by about their breadth; tergites not mem- 

 branous in apical middle. 



Head and thorax black above, yellowish piceous below ; the latter 

 color embracing the face, cheeks, lower part of propleura and 

 pronotum, mesosternum, mesopleurum along posterior suture, and 

 more or less of metapleurum and side of propodeum; clypeus and 

 mandibles yellow; coxae piceous; paler toward apex; trochanters 

 and bases of femora yellowish testaceous as are also the underside 

 of front and middle tibiae, front tarsi and calcaria; legs otherwise 

 black; wings deep black; abdomen rufous, the sternites and edges of 

 apical tergites darker. 



Male. — Differs in having head except clypeus and mouth parts, 

 thorax and legs except apices of trochanters and calcaria entirely 

 black. 



Host. — Arge salicis. 



Type locality. — Ammons, Breckinridge County, Kentucky. 



Type.— C?it. No. 24626, U.S.N.M. 



Described from three females and six males reared by Prof. H. 

 Garman from cocoons of host collected in drift along Ohio River. 



The smallest specimen, a female, is 6 mm. long with antennae 

 practically as long as body. Paratype a, female, has the sternites 

 and edges of the tergites almost black. 



The type, allotype, and four paratypes are in the National Museum 

 and three paratypes returned to Professor Garman. 



The following key will separate the North American species of 

 Boethus: 



KEY TO NORTH AMERICAN SPECIES OF BOETHUS. 



1. Gastrocoeli of second tergite longitudinal; mesopleuruin with a punctiform 



fovea near posterior margin ; intercubitus nearly or quite as long as second 



abscissa of cubitus ; nervellus broken at lower fourth 2. 



Gastrocoeli transverse ; mesopleurum without fovea ; Intercubitus much 

 shorter than second abscissa of cubitus ; nervellus broken at or above lower 

 third ; first tergite not or barely half as wide at apex as long 3. 



2. Thorax below and abdomen largely black aenigmaticus Viereck. 



Thorax and abdomen entirely red; first tergite fully two-thirds as wide at 



apex as long alaingens Davis. 



3. Thorax at least dorsally red, adbomen largely black; wings fuscous. 



schizoceri Howard. 

 Head and thorax mostly black or piceous, abdomen red 4. 



4. Thorax red dorsally; 5 mm glabranotus Davis. 



Thorax black dorsally, sometimes more or less reddish veutrally ; S uiru. ; 



wings deep black nigripennis Cushmau. 



