A REVISION OF NORTH AMERICAN CHRYSOBOTHRINI 31 



a shallow depression an each side near apical angle ; surface coarsely, densely, uni- 

 formly punctate, sparsely clothed with short, erect, inconspicuous hairs, the inter- 

 vals densely, finely granulose. 



Elytra slightly wider than pronotura, twice as long as wide; sides slightly 

 sinuate behind humeral angles, arcuately expanded behind middle, then arcuately 

 converging to the tips, which are separately broadly rounded; lateral margins 

 slightly serrate ; basal depressions broad and deep ; humeral depressions elongate 

 and shallow; disk moderately convex, with vague, longitudinal costae, surface 

 coarsely, deeply, rather sparsely punctate basally, more finely punctate toward 

 apices, sparsely clothed with short, erect, whitish hairs, the intervals obsoletely 

 granulose. 



Abdomen beneath sparsely, coarsely, irregularly punctate, sparsely clothed with 

 rather short, recumbent, inconspicuous hairs, without lateral callosities, the 

 intervals finely, densely granulose; last visible sternite rather deeply, arcuately 

 emarginate at apex, without a submarginal ridge, the lateral margins slightly 

 serrate ; eighth tergite broadly, triangularly emarginate at apex, finely granulose, 

 coarsely, densely punctate, but not longitudinally carinate. Prosternum coarsely, 

 densely punctate, sparsely clothed with long, semierect, white hairs; anterior 

 margin strongly deflexed, with a distinct, wide, short, median lobe. Anterior 

 femur with a short, obtusely triangular tooth, which is dentate on outer margin. 

 Anterior and middle tibiae arcuate, the former with a short, rounded dilation at 

 apex ; posterior tibia straight. 



Length 9.25 mm., width 3.5 mm. 



Redescribed from the male lectotype, No. 3442, in the Academy of 

 Natural Sciences of Philadelphia. 



Female. — Differing from the male in having the antenna uniformly piceous, the 

 last visible sternite more elongate and slightly emarginate at apex, the eighth 

 tergite shallowly emarginate at apex, the middle tibia straight, and the anterior 

 tibia unarmed at apex. 



Type locality. — California. The lectotype is simply labeled "Calif.," 

 but Horn states that it occurs in the mountain regions of northern 

 California near Yreka and Mt. Shasta. 



DISTRIBUTION 



From material examined: 



Caufoenia : Yreka, Paradise Valley, Kings River, July 16, 1917 (R. L. Beardsley). 

 Yosemite, altitude 3,880-4,000 feet, June 18, 1928 (E. F. Wohletz). Alder 

 Creek, Yosemite National Park, July 26, 1915 (H. G. Champion) . Los Angeles 

 County, July (D. W. Coquillett). Mather, July 19, 1938 (E. G. Linsley). 

 Towle, June 25, 1933; Dead Man's Creek, Mono County, July 25, 1936; 

 Dardanelle, Tuoloumne County, June 27, 1937 (M. Cazier). 



Oregon : Ashland, June 25, 1915, June 24, 1916 (F. P. Keen). 



Chamberlin (1917, 1926) reports it as being rare but widely distri- 

 buted throughout the Cascade Sierra region, and records it from the 

 following localities in California : Lake Tahoe, Pasadena, Bishop, and 

 Shasta and El Dorado Counties. 



Hosts. — The adults have been collected by different collectors in 

 Oregon and California on the flowers of wild buckwheat (Eriogonum 

 sp.) . Chamberlin (1925) records it as breeding in yellow pine (Pinus 

 ponderosa Lawson ) twigs, but this host record should be verified. Beer 

 (1940) records collecting the larvae in the woody roots of wild buck- 

 wheat (Eriogonum nudum) and states that many of the larvae had 

 been destroyed by parasites. 



This species shows considerable variation in color and size. As in 

 many of the blue and green species of this genus, the color varies 

 from golden green through blue to violet, with all intermediate 

 shades. The pronotum is usually widest at the middle where the 



