772 BOSTON JOURNAL 



ANDRENA Fabr. King. 



A. VALIDA. — $ Entirely black, immaculate; hair very short, 

 dense, giving to the thorax and head a velvet-like appearance : 

 head with the hair of the cheeks, tip of the nasus and outer in- 

 ferior edge of the mandibles longer : mandibles with a rather 

 strong tooth before the tip : wing-scale glabrous : wings purplish- 

 fuliginous, the darkest portion at tip ; stigma honey-yellow : me- 

 tathorax, surface not concealed by hairs, with separate punctures 

 and except at base, canaliculate in the middle ; at base is a trans- 

 verse space of much larger, confluent punctures, behind which 

 space is a narrow glabrous space at the origin of the groove ; 

 lateral margin hairy : tergum with very short hairs not conceal- 

 ing the surface ; first segment concave and deeply canaliculate 

 on the anterior face ; segments with a transverse, impressed, sub- 

 marginal, posterior line ; on the first and second are two : venter, 

 segments with long, rather dense hairs. 



Length seven-tenths of an inch. 



A large and fine species. [394] 



HALICTUS Latr. 



1. H. NIGRICORNIS Fabr. {Centris.) This appears to be the 

 male of H. viridula Fabr. {Megilla), and the same as IT. nigri- 

 rornis Coqueb. (Andrena) and H. sericea Forster. 



2. H. RADIATUS. — 9 Green ; metathorax behind with a radi- 

 ated disc. 



Inhabits Indiana. 



Body green, polished ; hairs numerous, short, cinereous, not 

 obscuring the general color : antennae black, more or less tinged 

 with piceous, particularly beneath : nasus before black, ciliate ; 

 labrum piceous : mandibles yellow towards the base, piceous at 

 tip : wings tinged with fuliginous ; nervures brownish, supple- 

 mentary nervure at tip of the radial cellule very distinct : meta- 

 thorax at base having numerous, elevated longitudinal or oblique 

 lines ; on the posterior declivity is a somewhat orbicular disk, 

 distinguished from the general surface by an elevated line equally 

 distinct all around ; it is radiated with elevated lines : tergum 

 sometimes tinged with blue or purplish ; each segment with a 



[Vol. I. 



I 



