Il6 CALIFORNIA ACADEMY OF SCIENCES. 



and deeper, and by the coarse sculpture of abdomen. It 

 is very likely that what Cresson has described as the male 

 of mexicanus, really does not belong to that species, but 

 is on the contrary the 5 of scaber, as it appears to be 

 more closely related to the latter than to the former. 



Perdita ventralis Fox. Magdalena Island (Haines), 

 March. Numerous specimens, among which are several 

 females, which sex is not described. Owing to an error, 

 whether on my part or the printer's, in the original de- 

 scription the sex is marked ? , when it should have been 3 . 



$ . — Cheeks unarmed; frontal impressed line distinct, 

 but not strong; mandibles medially, antennae beneath, 

 tibiae, tarsi, apex of fore and posterior femora, tegula;, 

 the ventral abdominal segments entirely, and an irregular 

 band on dorsal segments 2-5, emarginate behind and 

 sometimes interrupted medially, all yellow, otherwise as 

 in the 3 . 



Nomada sp. A specimen from San Jose del Cabo, 

 July, which may be but a variety of JSf. Kriigu Cress., 

 from Porto Rico. 



Epeolus texanus Cr. Two specimens. San Jose 

 del Cabo and Todas Santos, October. 



Epeolus occidentalis Cr. San Jose del Cabo, Oc- 

 tober. Two specimens. 



LiTHURGUs OBLONGUS Fox. Four Specimens. San 

 Ignacio (Haines), April. 



Megachile Sayii Cr. El Taste, 3,400 feet. Two ? 

 and six 5 specimens. 



Megachile mexicana Cr. One specimen. ElChinche, 

 September. 



Megachile spp. Two species, which I am unable to 

 identify, one of which may be J/. Candida Sm., but the 



