143 



is no greater than for instance between Lciopodus and certain Epeolus 

 or between Melectn and certain Crocisa. 



Table of Genera. 



A. — Middle tibial spur entire; marginal cell not extending beyond third 

 submarginal. 

 B. — Scutellum strongly bitubereiilate, the tubercles shortly tooth- 

 tipped; flagellum normal- ■ Melecta 



BB. — Scutellum broadly bilobed; flagellum greatly swollen; abdomen 

 but little longer than broad 



Micromelecta n. gen. 

 (type — M. maculata Cr.) 

 A A. — 'Middle tibial spur bidentate; scutellum broadly roundly bilobed; 

 marginal cell extending far beyond third submarginal; submar- 

 ginal cells strikingly different in the two sexes; flagellum 



normal Ericrocis. 



In a large series of Melecta from Colorado, Arizona. Nevada and Ca- 

 lifornia, I am unable to separate the mhanda of Fox from the califor- 

 nica of Cresson, except as a variety, since some of the Nevada forms 

 are fairly intermediate. Still I must say that I have not seen Dakota 

 specimens. In my collections are also several specimens of Micromelec- 

 ta maculata from Arizona, collected by Oslai-. 



In coming to re-examine some Arizona Ericrocis on which, follow- 

 ing others, I had placed the Texan name lata, the conclusion was 

 finally reached that they were not lata, at all, and that there were 

 before me two good species in place of one. In both of these the 

 scutellum is pale with two large black spots, — a character which 

 would surely have been mentioned for lata had it occurred. Cresson 



says only, "a patch behind scutellum clothed with black 



pubescence". The species may be separated by the following table: 



Ericrocis 

 A. — S<?utellum covered with white pubescence, a black patch behind it 



(Texas) •• Inta Cr, 



AA. — Scutellum white with two very large black patches occupying 

 most of its surface. 

 B. — Pubescence of face silvery white, on thorax pale; wings subh- 

 yline, with marginal cell, and apical border irregularly, fus- 

 cous ariznnensis n. sp. 



BB.— Pubescence of face, and thorax above, tawny; wings fuscous 

 throughout . . .^ melectnidea n. sp. 



4897 Ericrocis arizonensis n. sp. 



Male. Length 12 mm. Black; whole face above laJirum to midway 

 between antennae and ocelli completely covered with very dense silky, 

 white, appressed pubescence. Mandibles entirely jet black. The pubes- 



