AET. 2 REVISION OF TRIRHABDA NORTH OF MEXICO BLAKE 27 



Food flants. — Sagebrush, Artemisia sp. (LeConte), Aplopapims 

 squarvosus Hooker and Arnott (Blake), greasewood, Covillea trlden- 

 tata (R. S. Vaiie). 



Remarks. — There is one dark specimen of this in the Bowditch 

 collection labeled " Florida," and I have also examined four speci- 

 mens from the Horn collection labeled " New Jersey." These are 

 typical luteocincta^ two being vittate and two with dark-blue elytra, 

 appearing nearly black. I doubt the correctness of the labels, as 

 the species is otherwise known only from the coast of middle and 

 southern California. The aedeagus differs from that of most of the 

 species in its extremely long and tapering tip, but agrees in this 

 respect with two closely related California species, labrata and 

 confusa. 



16. TRIRHABDA CONFUSA, new species 



Flate 2, Figure 16 



Description. — Closely resembling luteocincta but smaller, with 

 less heavil)^ marked head and pronotum and paler ventral surface. 

 Head moderately coarsely punctate, and with long but not dense 

 pubescence, a broad dark occipital spot with metallic luster, usually 

 not covering base of head, and curving down front often to an acute 

 point, but rarely extending to eyes. xVntennae with third joint 

 shorter than fifth. Prothorax scarcely twice as wide as long, with 

 obtusely angulate sides ; surface shining, not greatly depressed, with 

 few scattered punctures; spots small, usually piceous, sometimes 

 with inconspicuous metallic luster, median one small, rounded or 

 diamond-shaped. Scutelium usually bicolored. Elytra finely and 

 densely punctate, with long silky pubescence, entirely blue or green 

 except for pale margin or occasionally vittate with pale median vitta 

 not reaching apex. Body beneath pale, frequently with dark metal- 

 lic margin to metasternum and abdomen. Legs entirely pale or 

 with only small darker spot on outer side of femora. Length, 7 mm. 

 to 8.5 mm. ; width, 2.8 mm. to 3.8 mm. 



Type. — Collected hj D. W. Coquillett in Los Angeles County, 

 Calif. U.S.N.M. No. 43022 (with 2 paratypes). 



Distribution. — California (San Gabriel, Los Angeles County, 

 Bakersfield, Lebec, Bishop, Yreka). 



Food plant. — Sagebrush, Artemisia sp. (R. Hopping). 



Remarks. — The prothorax of this species suggests in its shining 

 surface that of nitidicollis.^ but the long, dense, silky pubescence of 

 the elytra as well as the differently shaped aedeagus separates it 

 from that species. It is closely related to luteocincta and may be 

 only a regional variety, although the aedeagus is not exactly similar, 

 having a tapering tip, which is distinctly shorter and more pointed 



