July, '08] ENTOMOLOGICAL NEWS. 323 



Bees of the genus Nomada, belonging to the group of 



N. depressa Cresson. 



BY T. D. A. COCKERELL. 



In 1863 (Troc. Ent. Soc. Phil.), Cresson described a female 

 Nomada from" Maine as N. depressa, characterized especially 

 by the possession of a depressed velvety or pubescent area on 

 the apex of the fifth abdominal segment, much after the man- 

 ner of Triepeolus. Later, this insect was treated as a variety 

 of N. bisignata ; but it is not only a valid species, but perhaps 

 deserving of subgeneric rank. It typifies a little group, of 

 which four species are known, separable as follows : 



Depressed area on fifth segment very broad ; pygidial plate very broad ; 

 antennae entirely red, except a small black spot on scape 

 above ; mesothorax red, with one black band i. 



Depressed area much narrower, so that the space between it and the 

 base of segment at sides is as great as or greater than width of 

 of area 2. 



1. Length about 8 mm.; wings reddish, darker apically, with a subapical 



hyaline patch; stigma clear ferruginous; third antennal joint 

 distinctly shorter than fourth ; second abdominal segment with 

 a very large bright yellow patch on each side ; third, fourth 

 and fifth also each with a pair of yellow marks, growing suc- 

 cessively smaller and closer together (Falls Church, Virginia, 



May 20, Nathan Banks) N. depressicauda n. sp. 



Length about 9 mm.; wings dusky along the veins ; stigma dark red- 

 dish ; third antennal joint subequal with fourth ; second abdo- 

 minal segment with small and obscure yellow spots, the others 

 without yellow (Mt. Hood, Oregon)- - N. hcodiana Ckll., 1903. 



2. "Length S)4 mm.; mesothorax light reddish-brown, with median 



longitudinal black stripe ; metathorax red, with median black 

 stripe, sides at base black ; as much space between the flat- 

 tened area and base of segment at sides as the area is wide " 



(Maine) N. depressa Cresson. 



Length about 10 mm. ; mesothorax dark red, with a black band ; 

 metathorax black, with six red spots, the upper pair in the 

 enclosure, the middle pair rather obscure and more or less 

 confluent with the upper ; distinctly more space between the 

 flattened area and base of segment at sides than area is wide 

 (Lehigh Gap, Pa., June 30, Viereck) . . . N. skinneri n. sp. 



The last is the supposed A 7 , depressa referred to in Proc. 

 Phila. Acad., 1903, p. 608. I am greatly indebted to Dr. 



