294 HYMENOPTERA ACULEATA. 



It may be known at once from ochrostoma, which it most 

 resembles, by its smaller size, sharp mandibles, and the 

 three short black blnnt spines round the exterior apex of 

 the posterior tibiaj. This last character distinguishes it 

 from all the other species of the genus ; the third and 

 fourth joints of the antenna are subequal. 



L. 9 mm. 



Thomson describes this species from Sweden nnder the 

 name of rufilaliris. 



N. ruficornis, Linn, (flava, Kirb., signata, Jur.). — Head 

 and thorax black in the (J, sometimes nearly red in the ?, 

 closely punctured, densely clothed with brownish-grey 

 hairs in the c?, less densely with shorter brownish hairs in 

 the ? ; mandibles, labrum, clypeus, and sides of the face 

 ilavous in the S, ferruginous in the ?; mandibles acute, 

 piceous at the apex ; antennas fulvous, unicolorous in the ? , 

 moi'e or less black posteriorly, with the scape yellow in front 

 in the cJ, third joint about half the length of the fourth in 

 the c?, about three-quarters its length in the ?, face in 

 the c? clothed with silvei-y hairs below the antennas ; thorax 

 black in the (S , with the tubercles and tegulse testaceous in 

 both sexes, sometimes paler in the J, ? with the pronotal collar 

 ferruginous, mesonotum normally with four longitudinal ful- 

 vous stripes, these may become so wide as hardly to leave 

 any black between them, or become nari-ow or fragmentary 

 so that the whole mesonotum is nearly black, mesopleuraj 

 in the ? with a large red spot, scutellum in the (J black or 

 spotted with fulvous, in the ? fulvous, wings slightly 

 clouded, especially apically, propodeum finely rugose, some- 

 times spotted with fulvous in the ?, or in var. signata 

 with yellow ; abdomen finely punctured, shining, brown, 

 black at the extreme base, its mai kings varying from a 

 single yellow spot on each side of the second segment 

 and a square spot on the apical one, to an entire yellow 

 band on each of the segments, the apices of the segments 

 sometimes margined with black, basal segment often entirely 



