AMERICAN HYMENOPTERA. 381 



a sharp point, twice longer than it is wide at the base and continued as a stout 

 spine to the base of the apical fourth of the segment; the sides stoutly keeled ; 

 the bordering furrows shallow, obscurely striated; the curved lateral furrows 

 wide, deep. Suturiform articulation wide, finely striated in the middle. There 

 is a smooth, moderately broad, not very prominent keel on the basal two-thirds 

 of the 3rd segment, which has, shortly behind the middle, a smooth curved fur- 

 row; there being another on the 4th. Face alutaceous, opaque, the rest of the 

 head and the thorax smooth and shining; there is a narrow, finely margined 

 furrow in the centre of the front. Wings long; apical abscissa of radius dis- 

 tinctly longer than the basal two united ; the recurrent nervure is received in 

 the apex of the 1st cubital cellule, clearly separated from the transverse cubital. 

 Temples wide, obliquely roundly narrowed. Palpi yellow. The hind femora 

 bear an interrupted black line below; the hind coxa? are black. Tegula? luteous. 

 The thorax is sparsely haired. Parapsidal furrows fine, rufous colored towards 

 the apex. First abdominal segment as long as it is wide at the base. 



Hab.— Mam iva; Rio Purus (Prof. I. W. H. Trail). 



I phiaulax jutahiensis sp. nov. 



Black ; the sides of the middle segments and their apices narrowly rufous, the 

 stigma entirely pale ochraceous, the base of the radius testaceous, the wings 

 light fuscous, the base of the radial cellule, the first cubital and a narrow cloud 

 outside the recurrent nervure hyaline. Plate on 2nd abdominal segment trian- 

 gular, ending in a short point; its length, without the apical point, as long as 

 the width at the base ; it reaches close to the apex, from which it is clearly sepa- 

 rated. 9 • Length 12 mm. ; terebra 3 mm. 



Face and median segment thickly covered with longish grey pubescence; the 

 pleurae not so thickly with similar but shorter pubescence; the upper and lower 

 part of the propleurse more broadly bright red. Smooth and shining, except the 

 face, which is opaque, not smooth ; the clypeus above is bordered by a moderately 

 wide and deep furrow, bordered by distinct ridges. Frontal furrow narrow, 

 deep, reaching to shortly beyond the middle. Mandibles dark rufous to shortly 

 beyond the middle. Palpi black at the base, the apical joints dark testaceous. 

 Middle lobe of mesonotum distinctly separated. Middle lobe of first abdominaj 

 segment clearly separated, bounded laterally by a distinct furrow, which bears 

 at irregular intervals, some transverse keels; in the centre of the apex is a short, 

 stout, longitudinal keel, bordered by a furrow, wider than itself. The furrow 

 bordering the keel on the 2nd abdominal segment is stoutly, obliquely crenula- 

 ted, the oblique furrow distinct, narrow, smooth ; suturiform articulation closely 

 but not strongly striated. Underside of hind tarsi thickly covered with pale, 

 pubescence; the spines dark testaceous; the calcaria dark rufous. Apical abscissa 

 of radius about as long as the basal two united. 



Hab. — Amazonia; Rio Jutaha (Prof. I. W. H. Trail). 



This species is easily separated by the much broader (compared 

 with the length) plate on the 2nd abdominal segment. The fur- 

 rows on the 3rd and 4th abdominal segments are wide, almost 

 smooth. 



TBANS. AM. ENT. SOC. XXXI. (48*) OCTOBER, 1905. 



