94 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.47. 



harbecki Crawford. Sec under Anthidium. 

 *occidentale Cresson, 1868. New Mexico (S. Lewis). 



Colorado (cf. Cresson). 

 ridingsi Cresson. See under Anthidium.. 

 *zebratum Cresson, 1872. Texas (Heiligbrodt). 



Genus PROT ANTHIDIUM T. and W. Cockerell. 



This is an Asiatic genus; the two American species (cockerelli and chippewacnse) 

 whicii have been referred to it belong to Eeteranthidium. 



Genus TRACHUSA Jurine. 



A genus of Europe, represented in California by a single species, which departs from 

 typical Trachitsa, and approaches Dianthidium, in the venation. In general, however, 

 it is remarkably like the European T. serratulx. 



perdita Cockerell, 1904. Tehachapi, California (Davidson). 



Male about 12 mm.; abdomen black without light marldngs; clypeus and lateral 

 face marks cream color. 



Genus LITHANTHIDIUM Cockerell. 



pertriste Cockerell^ 1911. Fossil at Florissant, Colorado. 



Genus LITHURGUS Berthold. 



Fox (1902) has proposed to separate the North American species as a genus Lithur- 

 gopsis, but this can hardly be maintained. For an account of the characters of various 

 species of Lithurgits, see Trans. Amer. Ent. Soc, vol. 31 (1905), p. 333. 



Typical Lithurgus has no pulvillus in either sex ; the males of Lithurgopsis have a 

 distinct pulvillus. 



*apicalis Cresson, 1875. "Colorado, New Mexico (H. C. Yarrow, C. E. Aiken)." 



Hair at end of abdomen fulvou.s. 

 *apicalis opuntiae Cockerell, 1902. Mesilla Valley, New Mexico (Cockerell). 



Hair at end of abdomen dark. Formerly confused with, gibbosus. 

 *compressus Smith, 1853. "United States" (Doubleday). 



Apparently the male of gibbosus. 

 *echinocacti Cockerell, 1898. La Cueva, Organ Mountains, New Mexico (Townsend.) 



Visits Echinocactus wislizenii. 

 *gibbosus Smith, 1853. "United States." 



Female with the facial prominence not at all bilobed. 

 oblongus Fox= Megachilclongula. 



Lithurgus is known from the Eurppean Miocene (L. adamiticiis Ileer). It is repre- 

 sented in South America by the following species: 

 L. corumbse Cockerell. L. rvfiventris Frieso. 



L. dubius Sichel. L. pygmacus Friese. 



L. laticeps Friese. L. planifrons Friese. 



L. albiceps Friese. L. neoqueenensis Friese. 



L. huberi Ducke. L. osvwides Friese. 



L.friesci Ducke. L. macroglossa Friese. 



