414 Prof. 'P. D. A. Cockerel! on 



black ; hind coxa3 not spined ; apex of abdomen yellow, 

 broadly truncate, the sides of the truncation rounded, the 

 middle depressed, so that the apex is obscurely bilobed ; no 

 ventral spine. 



Bab. Gallinas River at La Cueva, Aug. G, 3 ^ {Porter & 

 CML). 



Previously known uidy by the unique type. A close ally 

 of this species, having a supraclypeal mark, the hind tibiae 

 black except at tlie ends, the abdominal band on the second 

 segment very broadly interrupted, the third to fifth segments 

 with only a large quadrate yellow mark on each side of the 

 middle, and a small spot at the extreme side, the sixth segment 

 with a broad angular or V-like band on each side, the apical 

 segment ivith four little teeth, is represented by a male col- 

 lected by Mr. E. M. Ehrhorn in the Mojave Desert, California. 

 The size is small (about 6 millim. long), and the punctures of 

 the scutellum are very dense and irregular instead of being 

 more or less in transverse rows as in gllense. The colour of 

 the wings, structure, and general type of markings agree so 

 well with gllense that 1 had no idea it was more than a colour- 

 variety until I saw the quite different apex of the abdomen. 

 For this Mojave Desert species I propose t\\t whihq Anthidium 

 Ehrhorni. 



A. Ehrhorni and A. gilense of the west, with A. notatum 

 and A. perplexuni of the east, form a compact group of 

 closely allied species. 



Anthidium occidentale, Cresson, 1868. 



Ilab. Sapello Canon, Aug. 31, 3 <?, 1 ? (TF. Porter); 

 San Ignacio, Aug. 31 and Sept. 1, 7 c?, 3 ? {Porter & CklL). 



This species will go with Anthidium proper for the present, 

 but with A. larrea' it really falls in a new group, which may 

 hereafter be separated. 



The range of A. occidentale is considerably extended by a 

 male from Custer, S. Dakota {L. Bruner, 18). 



Nomada modesta, Cresson, 1863. 



Ilah. Las Vegas, July 12 (A. Garlick), Aug. 1 (Porter ^ 

 CML). 



Nomada xanthophila, sp. n. 



^. — Length 11 millim. 



Black and yellow ; legs ferruginous and yellow ; antennas 

 ferruginous, black above ; apex of abdomen 2)^'oducedy nar- 

 rowly truncate^ entire. Resembles N. superba, Cress,, but 



