1865.] 487 



2. Pemphredon mandibularis, n. sp. 



Black; mandibles, scape of antennje beneath, tubercles, line on anterior tibise 

 and spot or annulus at base of four posterior tibise, whitish; wings hyaline, 

 dusky at tips; abdomen elongate, polished, petiole short. 



Female. — Deep black ; head and thorax subopaque ; head subquad- 

 rate, without distinct punctures; face and clypeus slightly silvery; 

 mandibles large, white, black at extreme tips which are broad and very 

 slightly emarginated ; scape of antennae beneath also white. Thorax 

 without distinct punctures; mesothorax with four longitudinal impressed 

 lines in front, becoming obsolete before reaching the posterior margin, 

 the two central lines very close together, leaving merely a narrow ridge 

 between them; scutellum flattened, quadrate, shining; metathorax sub- 

 quadrate, opaque, abrupt on the sides and behind, coarsely rugose; tu- 

 bercles whitish ; tegulae piceous-black. Wings hyaline, iridescent, 

 slightly dusky on the apical third; nervures fuscous. Legs black, seri- 

 ceous; anterior tibise with a whitish line in front, the two posterior 

 pairs with a whitish annulus at base, that on the middle pair indistinct 

 in one specimen; tarsi' piceous, paler at base. Abdomen elongate, sub- 

 cylindrical, smooth and polished, immaculate ; petiole very short. 

 Length 4 lines ; expanse of wings 6 lines. 



Two specimens. 



Genus MIMESA, Shuck. 

 1. Mimesa argentifrons, n. sp. 



Black; face bright silvery; antennae fulvous beneath; wings hyaline; meta- 

 thorax coarsely rugose ; second and third segments of abdomen rufous ; petiole 

 long and linear. 



Female. — Black, very minutely punctured; face, clypeus and cheeks 

 silvery, very brilliant; antennae as long as the head and thorax, slender 

 at base and gradually thickened towards the tips, black above, fulvous 

 beneath. Thorax clothed with a fine silvery pubescence, indistinct on 

 the mesothorax and scutellum, and most obvious on the metathorax, 

 which is coarsely reticulated, the enclosed basal space covered with 

 coarse longitudinal or slightly oblique striae ; mesothorax with two 

 faintly impressed lines in front; tegulae piceous. Wings hyaline, beau- 

 tifully iridescent; nervures and stigma black. Legs black or piceous- 

 black, clothed with glittering pubescence; tarsi fulvous. Abdomen 

 oblong-ovate, smooth and polished, sericeous and slightly pubescent at 

 tip, rufous; the petiole, spot on first segment above at base, apical 

 middle of the third, and the apical segments entirely, black or piceous- 

 black ; petiole about half the length of the remainder of the abdomen, 

 flattened and slightly grooved above ; apical segment flattened above, with 

 the sides subcarinate. Length 4 — 4J lines; expanse of wings 7 — 8 lines. 



