88 Clarence E. Mickel 
roe Canyon (7) and Sioux county (12); June 10 to August 15; 
visits flowers of Petalostemum sp. 
Psammophila valida (Cresson). 
1865. Ammophila valida Cresson, Proc. Ent. Soc. Phil., IV, p. 461. 
1903. Psammophila valida Melander, Psyche, X, p. 158. 
Males 4, females 8: Mitchell (1), Monroe Canyon (8) and 
Warbonnet Canyon (1); July 10 to August 20. 
Psammophila grossa (Cresson). 
1872. Ammophila grossa Cresson, Trans. Amer. Ent. Soc., IV, p. 200. 
1903. Psammophila grossa Melander, Psyche, X, p. 158. 
Females 34: South Sioux City (1), Lincoln (2), West Point 
(2), Holt county (1), Halsey (4), Mitchell (9), Glen (1), Mon- 
roe Canyon (5), Bad Lands (1) and Sioux county (2); June 2 
to September 12; visits flowers of Melilotus alba. 
Psammophila violaceipennis (LePeletier). 
1845. Ammophila violaceipennis LePeletier, Hist. Nat. Ins., Hym., 
IL, 9.2370. 
1903. Psammophila violaceipennis Melander, Psyche, X, p. 159. 
Males 111, females 9: Lincoln (4), West Point (1), Mitchell 
(35), Bridgeport (1), Halsey (2), Crawford (1), Pine Ridge 
(1), Glen (1), Bad Lands (1), Monroe Canyon (19), Sowbelly 
Canyon (2), Warbonnet Canyon (1) and Sioux county (16) ; 
June 10 to August 31; visits flowers of Melilotus alba and Mo- 
narda sp. 
SCELIPHRONINI 
KEY TO THE GENERA 
Transverse median nervure in front wings interstitial with the basal ner- 
vure; species metallic blue or violaceous; clypeus anteriorly three- 
dentate ; petiole of abdomen not or scarcely longer than the propodeum, 
Chalybion 
Transverse median nervure in front wings not interstitial with the basal 
nervure, but uniting with the median nervure a little before the origin 
of the basal nervure; species black and yellow, not metallic; clypeus flat, 
at apex bidentate; petiole of abdomen about twice as long as propodeum, 
Sceliphron 
406 
