1938] 
The Genus Lithurgus 
151 
Pubescence: Thin and greyish but rather long on vertex, 
whiter and more dense around antennae, at sides of face, 
and on cheeks behind and below, clypeus with an apical 
fringe which is white laterally but brownish medially; 
dorsum of thorax almost bare, pubescence laterally and 
beneath rather long, thin and greyish-white, whitish on legs 
basally, becoming more brownish apically, blackish on hind 
tarsi ; abdomen basally largely bare above, with very short 
dark pubescence evident laterally, segment 5 with relatively 
long conspicuous fuscous pubescence, that on segment 6 
fuscous and extremely dense; segments 2-5 with white 
apical fasciae, interrupted medially on segments 2-4; scopa 
yellowish, fuscous to black on segment 6 and with some of 
the same color on segment 5 across apical margin; sterna 
2-5 with entire white apical fasciae beneath scopa. 
9$, 44$, Bexar County (San Antonio), Texas. 1$, 
Austin, Texas, Apr. 16, 1933 (both H. B. Parks). 1 $ , Big 
Bend Park, Brewster Co., Texas, June 17, 1937, (R. H. 
Baker) . 
Lithurgus echinocacti Cockerell 
Lithurgus echinocacti Cockerell, Ann. Mag. Nat. Hist. (7) 
2, p. 453, 1898. Cockerell, Am. Nat. 34, p. 487, 1900. 
Cockerell, Ann. Mag. Nat. Hist. (9) 8, p. 368, 1921. 
Lithurgopsis echinocacti Fox, Ent. News 13, p. 139, 1902. 
This species bears some resemblance to socorroensis but 
differs from it in the following characters : 
$ — Prothorax with a distinct and conspicuous white 
fascia along its posterior margin; polished concavity of 
facial protuberance with scattered punctures; transverse 
process of labrum broader and less deeply emarginate. 
S — Prothorax fasciate as in $ ; supraclypeal area more 
closely and coarsely punctate ; labrum without a basal 
tubercle. 
Arizona : 1 $ , Coyote Mts., Aug. 3-7, 1916, about 3500 ft. 
[Am. Mus. Nat. Hist.]. Recorded from Palmerlee and 
Tempe (July and Aug.) . 
Lithurgus gibbosus Smith 
Lithurgus gibbosus Smith, Cat. Hym. Brit. Mus. 1, p. 147, 
1853. Cockerell, Am. Nat. 34, p. 487, 1900. Cockerell, 
