NORTH AMERICAN BOSTRICHIDAE 133 



Elytra at base subequal in width to pronotum along middle ; sides 

 slightly expanded posteriorly, conjointly broadly rounded at apices; 

 surface rather densely clothed posteriorly with short, recumbent, 

 white hairs, nearly glabrous on basal half, coarsely, densely, irreg- 

 ularly punctate on basal two-thirds, very sparsely, indistinctly punc- 

 tate on apical declivity ; sutural and lateral margins slightly elevated 

 on apical declivity ; each elytron with two large, mamillif orm tubercles 

 along anterior margin of apical declivity, the tubercles sometimes 

 acute at apices but not spinif orm. 



Abdomen beneath densely, indistinctly granulose, sparsely clothed 

 with short, recumbent, white hairs; last visible sternite broadly 

 rounded or subtruncate at apex. 



Female. — Differs from the male in having two small, distinct tuber- 

 cles on the front of the head, the first four visible abdominal sternites 

 narrower at the middle than at the sides, and the last visible abdominal 

 sternite longer than the preceding sternites united, opaque, densely 

 granulose and glabrous, and with a very deep, median emargination 

 which extends nearly to the base of the sternite. 



Length 2.75-4 mm., width 1.2-1.6 mm. 



Type locality. — Cape San Lucas, Lower California; types in the 

 LeConte Collection in the Museum of Comparative Zoology at Cam- 

 bridge, Mass. 



Distribution. — From material examined : 



Aeizona : Catalina Springs, April 12-15, Oracle, June 30 (Hubbard and Schwarz). 

 Hot Springs (H. S. Barber and E. A. Schwarz). Sabino Canyon, March 9, 1917 

 (G. Hofer). Redington and Santa Catalina Mountains (M. Chrisman). 



California: Palm Springs, July 11, 1932 (Blackwelder Collection). 



Lower California: Purissima, October 23 (W. M. Mann). 



New Mexico: Las Cruces, November 13, 1893 (T. D. A. Cockerell). 



Texas: Uvalde (W. F. Fiske). 



Hosts. — This species has been reared from paloverde (Oercidium 

 torreyanum (Watson) Sargent), mesquite (Prosopis julifiora 

 (Swartz) de Candolle), and catclaw (Acacia greggii Gray). 



LeConte described this species from two specimens collected by 

 Xantus. 



Genus XYLION Lesne 



Xylion Lesne, 1901, Soc. Ent. de France Ann. (1900) 69: 478, 542-564; 1924, 

 Bostrychides de l'Af rique Tropicale Franchise, pp. 209, 229-238 ; 1938, in Junk 

 (pub.), Coleopt. Cat., pt. 161, pp. 63-64. 



Head deeply inserted in prothorax, not visible from above, convex 

 or feebly, transversely depressed between eyes ; clypeus strongly trans- 

 verse, sinuate in front; labrum transverse, subtruncate and densely 

 ciliate with long, yellow hairs in front; mandibles attenuate toward 

 apices; eyes large, oblong, strongly projecting. Antennae 10-seg- 

 mented ; first and second segments robust, first oblong, slightly arcuate, 

 subequal in length to second; third to seventh segments short, com- 

 pact, transverse (except third), united shorter than first segment of 

 club; last three segments forming a large, loose, compressed club, 

 densely clothed with short, recumbent, yellowish hairs, each with 

 small, indistinct, sensory depressions on each surface, the eighth sub- 

 triangular, ninth round, and tenth oblong, narrower than ninth. 

 Pronotum strongly convex, truncate, or vaguely emarginate at base 

 and apex, dentate anteriorly, not transversely depressed behind an- 



