32 PROCEEDHsTGS OF THE NATIONAL MUSEUM vol.79 



cent; in darker specimens frequently with black occipital spot ex- 

 tending across head, about eyes, and down front, in paler specimens 

 this plaga reduced to a spot. Labrum usually piceous. Antennae 

 with third joint slightly shorter than fifth. Prothorax not twice as 

 broad as long, with shghtly arcuate sides, without angles; surface 

 alutaceous, densely and coarsely punctate, sometimes lightly pubes- 

 cent; spots black, of moderate size. Scutellum frequently bicolored 

 in paler specimens. Elytra densely and moderately coarsely but 

 shallowly and confluently punctate, with fine short pubescence; in 

 pale specimens with only traces of pale reddish-brown vittae; in 

 better marked ones with a wide reddish-brown sutural vitta and 

 lateral vitta and more feebly defined median one, not reaching base, 

 and uniting with lateral and sutural vittae near apex ; in dark speci- 

 mens elytra almost entirely piceous. Body beneath unusually pale 

 brown, deepening to reddish brown in dark specimens. 



Length, 5.5 mm. to 7 mm. ; width, 2.8 mm. to 3.5 mm. 



Type locality. — " Occurs at San Diego, California, and Arizona." 



Distribution. — Arizona (Tucson, Catalina Springs, northeast of 

 Tucson; Prescott, Nogales, Santa Rita Mountains), California (San 

 Diego, Claremont, Los Angeles, Idylwild). 



Food plant. — Encelia farinosa Gray (E. A. Schwarz), Bahia sp. 



Remarks. — Specimens from southern California near the coast are 

 darker in their markings than many of the inland specimens. One 

 from Idylwild, Calif, (collection of Kansas University), has elytral 

 marldngs similar to those of canadensis.^ with no trace of a median 

 vitta, although the others of the same series are typically colored 

 dark specimens. 



DEROSPIDEA, new genus 



Oblong, subparallel, robust. Head glabrous, vertical, a median line 

 over occiput and front; antennae with fourth joint longer than third, 

 third and fifth subequal. Prothorax considerably more than twice 

 as broad as long, depressed, lateral margins arcuate, tending to be 

 obtusely angulate at middle. Scutellum truncate. Elytra oblong, 

 pubescent, indistinctly margined, epipleura becoming indistinct 

 behind middle. Tibiae feebly grooved for less than their entire 

 length, first tarsal joint longer than second, claws bifid. Aedeagus 

 short, with broad truncate tip. 



Type of genus. — Trirhabda hrevicollis LeConte. 



This genus is distinguished from Trirhahda by the prothorax, 

 which in Trirhabda is approximately twice as broad as long ; by the 

 aedeagus, which is short and broad and without a pointed tip, and at 

 its base has a wider and thickened chitinous band with distinct free 

 tips on the ventral side; and by the pattern of coloration and 

 pubescence. In Trirhabda there is always a well-marked occipital 

 spot and the occiput is always pubescent, usually conspicuously so. 



