394 



SayU Descriptions of 



Halictus, Latr. 



\ 



1. H. nigricornisj Fabr. (Centris). This appears 

 to me to be the male of H. viridula, Fabr- (Megilla), 

 and the same as H- nigricornisy Coqueb. (Andrena) 

 and H. sericeay Forster. . , ^ 



2. H. radiatus. 9 Green ; metathorax behind with 

 a radiated disc. 



Inhab. Indiana. 



Body green, polished ; hairs numerous^ short, cinere- 

 ous, not obscuring the general color : antennce black, 

 more or less tinged with plceous, particularly beneath : 

 nasus before black, ciliate ; lahrum piceous : mandibles 

 yellow towards the base, piceous at tip : wings tinged 



T '1 



with fuliginous ; nervures brownish, supplementary ner- 

 vure at tip of the radial cellule very distinct ; metathorax 

 at base having numerous, elevated longitudinal or oblique 

 lines ; on fhe posterior declivity is a soriiewhat 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 slight inequality or impressed trans- 

 verse line, near the middle : feet dark piceous ; tarsi and 

 knees somewhat paler. 



^nw 



Length over two fifths of an inch. 



I 



3. H. lahrosus. 9 Greenish ; tergum purplish, seg- 

 ments margined with blackish. ' 

 Inhab. Mexico. 

 Body green, with a purple reflection : antenncE black: 



nasus 



at tip blackish : lahrum black, much elevated at the 



middle of the tip ; the elevation grooved before : mandi- 

 bles black, tinged with piceous at tip : wings hyaline, 

 slightly tinged with fuliginous ; nervures fuscous : nieia- 



