70 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES. 

 Hymenoptera of Southern California. — I. 



BY T. D. A. COCKERELL. 



Pogonoinyrinex calif oniiciis, Buckl. San Pedro, 1901. 

 (Cockerell). Determined by Prof AA\ ]\I. \Mieeler. 



Stcnanuiia {Mcssor) aiidrei, ]Mayr. La Jolla, San Diego 

 Co., 1901. (Cockerell). Determined by Prof. \A'. AI. Wheeler. 



Agaposfcmoii tcsauiis. Cresson. San Pedro, Julv. (Cock- 

 erell).^ 



Agapostcnioii califoniiciis, Crawford. San Pedro, July 8. 

 (Cockerell) ; La Jolla, August. (Cockerell). 



Zacosiiiia uiacidata (Cresson). San Pedro, Tulv 10. ( Cock- 

 erell) . 



Boinhus califoniiciis. Smith. A ariety with face of female 

 covered with yellow hair. San Pedro, July 8. (Cockerell) . 



Megachile davidsoni. n.sp. Female, length 16 mm., black. 

 Allied to M. chilopsidis, Ckll., but differing as follows: Larger; 

 mandibles broad and massive at base, having beneath a large 

 concavity, bounded on the distal side by a projecting tooth-like 

 rim ; inner edge of mandibles without an orange fringe ; the inner 

 side broad and concave, and the upper margin of the mandibles 

 near base produced into a large thick ascending tooth ; clypeus 

 shining, with sparse strong punctures, produced into a couple of 

 large, thick triangular processes, standing at right angles to the 

 face, and separated by a wide interval ; thorax less hairy, no white 

 hair-band between mesothorax and scutellum. This agrees with 

 chilopsidis in the massive occipital region, the wide opening be- 

 tween the mandibles, the close punctures of head and thorax, the 

 simple antennje, the ventral scopa yellowish-white or white, black 

 on the last segment, etc. 



This is a most extraordinary insect, and it is much to be 

 desired that its habits should be observed, so as to explain the 

 meaning of the "peculiar clypeus and manibles. The process on 

 the face suggests at first that the insect may be a Litluirgiis, but 

 it is a veritable Megachile. as is indicated bv the sculpture, 

 tarsi, etc. 



Two specimens from Southern California, collected by Dr. 

 A. Davidson. One from near Los Angeles ; the other from 

 Switzer's Camp. 



Megachile angelannii, 11. sp. Female, length ii}^ mm., black, 

 abdomen parallel-sided, rather narrow, with narrow white hair- 

 bands ; ventral scopa white, black on last segment ; hair of head 

 and thorax white or whitish, very scanty above; no hair-band 

 between mesothorax and scutellum, nor white patches on anterior 

 part of mesothorax ; antenna? short. Allied to M. prosopidis. Ckll., 

 but differs as follows: Smaller; broad apical margin of mandi- 

 bles with two teeth at apex, and a notch near inner angle; semi- 

 circular excavation of anterior margin of clypeus without a me- 



