Studies of North American Bees 3 



in f otitis), strongly bigibbous mesoscutellum (scarcely so in 

 fontis), unilineate mesoscutitm (trilineate in fontis), more exten- 

 sively black propodeum, lack of yellow on corners of face, etc. 

 From N. packardiella Ckll., it differs at once in its much smaller 

 size, dark flagellum, shorter third antennal joint and copious, 

 wholly white pubescence. The black median mesoscutal line, 

 mostly black propodeum, black areas on base of abdomen, about 

 antennal bases and ocelli, together with the copious pubescence, 

 especially on the sides of the propodeum, distinguish it at once 

 from N. nigrofasciata Swenk. N. pulsatillae Ckll. can easily be 

 told by its flattish, non-gibbous mesoscutellum, fuscous hair of 

 head and thorax above, longer third antennal joint, lack of 

 yellow on abdomen, etc. 



The male resembles N. undulaticornis Ckll. (which is probably 

 the (^ of N. pulsatillae) , but is much smaller, has less yellow on 

 the clypeus and sides of the face, the third antennal joint much 

 shorter, the mesoscutellum evenly convex and wholly black, the 

 nervures pale testaceous, etc. It is exceedingly close to A^. ida- 

 Jwensis Swenk, and were it not for the feebly but distinctly 

 bigibbous mesoscutellum and the basal nervure being considerably 

 basad of the transverso-medial nervure in idahoensis, one would 

 certainly consider them conspecific ; in addition suhnigrocincta J* 

 differs from idahoensis in the broader and yellower apical band of 

 the clypeus, the yellow labrum, the scape and third antennal joint 

 being pale beneath, the black line on antennae above narrower, 

 apically broken and merely dusky, the more extensively blackish 

 tergum, the lack of subdiscal yellowish spots on tergite 5 and the 

 yellow marks on venter being obsolete. 



Nomada (Nomada) depressicauda Cockerell. 



A female is before me from Germantown, Pennsylvania, col- 

 lected April 21, 1905. This is the third recorded locality for the 

 species, it having been previously collected in Virginia and 

 Nebraska. 



Nomada (Nomada) sayi Robertson. 



Before me is a pair from Germantown, Pennsylvania, May 6, 

 1905 (5), and May 7, 1905 {<$). Also two males from Glen- 



157 



