NORTH AMERICAN HYMENOPTERA. 173 



anteriorly ; scutellum sparsely punctured ; mcsopleurse punctured about like the 

 dorsulum, but more regularly so, the fovese of the episternal suture scarcely evi- 

 dent ; sculpture of middle segment indistinct, above appearing longitudinally and 

 finely striated, the sides and posterior face subtilely sculptured, lateral ridges of 

 the latter absent ; abdomen broader than in vernalis, not much narrovred to the 

 first segment. Black, including the mandibles; scape, two spots on pronotum, 

 tubercles, line on scutellum, apex of all the femora, tibiae entirely, tarsi except 

 apical joints, a large wedge-shaped spot on segments of abdomen 1-4, a bknd on 

 segment 5, and lateral spots on ventrals 2 and 3, bright yellow ; head, thorax and 

 first segment of abdomen with unusually long, shaggy, yellowish brown hair; 

 wings fulvo-hyaline. somewhat darker apically, nervures and stigma yellowish ; 

 no silvery pubescence, instead the long hair. Length 9-10 mm. 



% . — Sculptured like the 9 , but the middle segment is distinctly striated above, 

 as well as on the sides, and the punctuation of mesopleurge is closer ; space between 

 the hind ocelli very much less than that between them and the nearest eye- 

 margin ; antenufe longer and slenderer than in vernalis, acuminate at tip ; pro- 

 notum angular laterally; marks on scutellum sometimes wanting, those on the 

 scutellum not present, markings of abdomen smaller than in the f , those on 

 fifth segment generally separated, the sixth segment, however, banded ; wings 

 paler than in 9 ' clypeus black, with the inner orbits clothed with silveiy pu- 

 bescence; fore trochantej's almost equaling their femora in length, not much 

 broadened apically ; tibial shield larger and broader than in vernalis : basally it 

 is about as broad as long but narrows considerably behind, in color yellow, and 

 medially with irregular dark streaks, at the base broadly margined with black ; 

 first joint of medial tarsi distinctly longer than the remaining joints combined. 

 Length 8 mm. 



Nevada. I have seen no specimens measuring less than 8 mm. ; 

 Kohl gives 7 mm. as the smallest. As in vernalis, the males possess 

 no furrow between the epiraeruju mesopleuralis and the mesosternura. 



51. Crabro vernalis Pack. 



Thyreopus vernalis Packard, 1. c, p. 369, 9- 



Crabro vernalis Kohl, 1. c, p. 585. 

 9. — Head with the sculpture subtile, indistinct; first joint of flagellum about 

 as long as the two following united ; space between the hind ocelli .somewhat 

 greater than that between them and the nearest eye-margin ; lateral impressions 

 of vertex very shallow ; pronotum but slightly furrowed at the sides anterioi-ly, 

 the lateral teeth small and blunt; dorsulum with sparse, shallow punctures, 

 densest anteriorly ; scutellum scarcely punctured ; mesopleurse with the punctures 

 slightly stronger than those of the dorsulum, the episternal suture rather strongly 

 foveolate; middle segment above longitudinally and rather finely striated, more 

 distinctly so in some specimens than in others, the posterior face and sides sub- 

 tilely roughened, the lateral ridges of posterior face very short ; abdomen fusiform, 

 the first segment broad at apex, not tumid. Black, including the mandibles and 

 clypeus; scape at apex, large spots on pronotum, tubercles, scutellum, metanotum, 

 tips of fore and medial femora, tibiie except a line within and apex of hind pair, 

 first joint of tarsi, a wedge-shaped spot on dorsal abdominal segments 1-3, nar- 

 rower marks on segment 4, and a continuous line on segment 5, whitish ; head 

 and thorax clothed with thin, long, pale pubescence ; no silvery pubescence on 

 cheeks or thorax ; wings subhyaline. Length 7.5-9 mm. 



TRANS. AM. ENT. SOC. XXII. JUNE. 1895. 



