Studies of North American Bees 99 



pale (only the anterior margin laterally pale in the type of 

 rhodomelas) , the mesoscutellum red and the scape with a broad 

 red line in front (both wholly black in the type of rhodomelas) , 

 and the apex deeply notched. The venation, however, is that of 

 rhodomelas, the second submarginal cell being very narrow with 

 the first recurrent nervure received much beyond its middle. The 

 red mesoscutellum and scape in front suggest A^. perhella 

 Viereck J*, but the venation and the pale red ground color of the 

 abdomen would indicate that it is not that species. 



Nomada (Gnathias) perplexans Cockerel!. 



1910. Noviada (Gnathias) perplexans Cockerell, Psyche, XVII, pp. 

 94-95, (^■ 



Two males from Washington State, one from Pullman, May 

 27, 1897, and the other from Wawawai (C. V. Piper), seem 

 referable here. They do not agree exactly with the description 

 of the type, collected at Pullman, having the mesoscutellum red, 

 round yellow dots on sides of abdominal tergite i and yellow 

 spots on sides of tergites 3 and 4 (and in one specimen on sides 

 of 5 also), the pair oi spots on 6 distinct and yellow, the clypeus 

 wholly yellow or nearly so, the first recurrent nervure joining the 

 broad second submarginal cell at its middle and the hair of the 

 thorax above not tinged with yellowish. The specimens are 9 

 and 8.5 mm. long, respectively. The venation of this form is 

 like that of A'', perhella, but the pale red abdomen, largely pale 

 clypeus, red mesoscutellum, etc., are very like that in the Van- 

 couver specimen referred above to rhodomelas, and may be the 

 same. The fact is, the northwestern species of this subgenus are 

 very poorly understood, and there will probably be a very dif- 

 ferent alignment of the species as more material accumulates 

 and is studied. 



Subgenus Melanomada Cockerell, 1903 



KEY TO THE NEBRASKA SPECIES 



Females 



Larger, 6.5-7 vam. long grindeliae 



Smaller, 4.5-5.5 mm. long heleniella 



99 



