ART. 23 REVISION" OF MACEOCENTEUS MUESEBECK 23 



13. MACROCENTRUS ATRATUS. new species 



Agrees with im-presstis and differs from all other related species 

 in having lower abscissa of basella longer than nervellus and about 

 half as long as mediella. It is at once distinguished from impressus^ 

 however, by being mostly black. 



Female. — Length 5.5 mm. Head a little wider than thorax; eyes 

 very large; malar space much less than basal width of mandible; 

 face strongly impressed medially above, mostly smooth except just 

 above clypeus where it is closely finely punctate; clypeus strongly 

 convex, truncate at apex; ocell-ocular line hardly one and one-half 

 times the diameter of an ocellus; temples and cheeks very narrow, 

 strongly receding; maxillary palpus long, the longest segment much 

 longer than second segment of antennal flagellum and nearly as long 

 as the first; apical segment of labial palpus much lengthened; an- 

 tennae longer than the body, 49-segmented. 



Thorax with prescutum prominently convex, descending abruptly 

 in front; notauli foveolate only behind; propodeum finely sculptured 

 except at base, more or less delicately obliquely aciculate; metapleural 

 tooth prominent; mesopleura not impressed below, smooth, shining, 

 with only scattered punctures; teeth outwardly at apex of trochan- 

 ters conspicuous; stigma rather long, much more than twice as long 

 as wide, emitting radius from much beyond middle ; radial cell end- 

 ing considerably before wing apex; first abscissa of cubitus straight, 

 the second about half as long as recurrent; first discoidal cell very 

 long, much longer than first cubital ; nervulus postf ureal by scarcely 

 half its length ; submedian cell weakly hairy apically ; lower abscissa 

 of basella half as long as mediella and somewhat longer than ner- 

 vellus ; radiellan cell widening slightly apically. 



Abdomen a little longer than head and thorax combined; first 

 tergite twice as long as broad at apex, impressed at base, finely lon- 

 gitudinally aciculate, the spiracles beyond basal fourth; second tergite 

 longer than broad, finely longitudinally aciculate, the smooth lateral 

 depressed margins narrow at base, the sculptured part of the tergite 

 as wide at base as at the middle ; third tergite longitudinally aciculate 

 on basal half; ovipositor sheaths a little longer than the body. 



Head black; clypeus entirely ferruginous; palpi whitish; man- 

 dibles whitish at base; basal half of antenna, including scape and 

 pedicel, brownish black, apical half paler; thorax blackish, with 

 sternum and pleura mostly brownish yellow or ferruginous; legs 

 yellow ; wings hyaline ; stigma and veins brown, the former not pale 

 at base ; abdomen black. 



ry/?e.— U.S.N.M. No. 43498. 



Type locality. — Ithaca, N. Y. 



Paratype locality. — Bar Harbor, Me. 



