ART. 2 REVISION OF TRIEHABDA NORTH OP MEXICO BLAKE 25 



Distribution.— Utah. (Washington County) ; California (Los 

 Angeles County, Claremont, Cajon Pass, Mojave Desert, Pasadena, 

 Mount Wilson, Chino Canyon) . 



Food plant. — Eriodictyon sp. 



Remarks. — In this species the diiierence in size of the sexes is 

 very apparent, the male being sometimes a third smaller than the 

 female. The shining prothorax resembles that of nitidicoUis, but it 

 is usually more depressed and not so long. The elytral vittae are 

 usually much less marked than in nitidicoUis, there being in most 

 specimens no evidence of sutural vitta beyond a slight darkening 

 of the sutural edges. The aedeagus is short and rather blunt. Ex- 

 cept for one specimen in the Casey collection labeled Washington 

 County, Utah, I have seen specimens only from southern California. 



14. TRIRHABDA DIDUCTA Horn 



Plate 1, Figure 14 

 Trirhahda diducta Horn, Trans. Amer. Ent. Soc, vol. 20, p. 70, 1893. 



Description. — Elongate, subparallel, pale yellow-brown, with shin- 

 ing, 3-spotted prothorax; elytra with blue, green, or purple 

 sutural and lateral vittae, usually also a narrow median vitta, not 

 reaching base and uniting with lateral vitta toward apex. Head 

 punctate over occiput and front, lightly pubescent, a moderately 

 broad, black, oblong spot on occiput extending down front. An- 

 tennae with third joint slightly shorter than fifth. Prothorax ap- 

 proximately twice as broad as long, with arcuate sides, scarcely angu- 

 late; surface shining with scattered coarse punctures; spots black, 

 moderate in size, often becoming small and diamond-shaped. Scutel- 

 lum piceous, frequently with pale apex. Elytra finely and obsoletely 

 punctate, pubescence fine, short, and dense; sutural and lateral 

 vittae usually not wide, a narrow median vitta frequently arising 

 before middle and uniting with lateral vitta before apex, this median 

 vitta often faint and evanescent; lateral and sutural vittae usually 

 uniting at apex, with blue, green, or purple luster. Body beneath 

 pale with margin of metasternum and abdomen sometimes darkened. 

 Length, 6.5 mm. to 9 mm. ; width, 2.5 mm. to 4 mm. 



Type locality. — "Western Nevada and adjacent regions of Cal- 

 ifornia." 



Distribution. — Nevada; California (Mokelumne Hill, Tulare 

 County, Mount Tamalpais, Santa Clara County, Fresno, Ahwahnee). 



Food plant. — Eriodictyon calif ornicum (Hooker and Arnott) 

 Greene. 



