388 Annals Entomological Society of America [Vol. X, 



carinatc, broadly curving, as long as the head. Pronotum slightly 

 bisinuate at base, with a strongly impressed median dimidiate longi- 

 tudinal stria; marginal stria strong, extending around i^osterior angles, 

 sharply broader anterior to the middle and terminating in a large 

 fossa (cf), gradually widening and temiinating in a small fossa (9), 

 at some distance Ijehind the anterior angles; anterior to the fossa, the 

 surface of the pronotum is rugose and from this rugose area, a fine stria 

 extends along the anterior margin to a point behind the eye; posterior 

 to this stria there is a short broadly impressed stria, which extends 

 beyond the marginal about one-half its own length; margin of pro- 

 notum with the marginal stria irregularly punctate, most densely just 

 ])osterior to the fossa, the punctures more sparse posteriorly and extend- 

 ing along the posterior margin half way to center. Elytra bistriate, the 

 first short, about one-third the length of the elytra, continued along 

 basal margin to the second, with which it sometimes connects, con- 

 tinued to the apex by a series of distant punctures; the second stria 

 entire, and continued along basal margin of elytra almost to the scu- 

 tellum; subhumeral deep, abbreviated at base under humerus, but 

 sometimes continued almost to the base by a few punctures. Elytra 

 distinctly punctured towards apex. Inflexed portion of elytra rugose. 

 Propygidium coarsely and fairly evenly punctate, most coarsely at 

 lateral margins. Pygidium coarsely but not very densely punctate. 

 Mentum slightly concave, densely, strigosely punctate laterally and 

 at corners, sparsely pvmctulate at center. Prosternuin elevated, con- 

 stricted in apical fourth, slightly depressed anterior to the constriction, 

 and again elevated at apex, truncate. Ventral segments of abdomen 

 punctate throughout. Lower crest of fore tibiae dentate. Length 

 8-9 mm. 



Distribution, San Diego, Co., Pasadena, California. 



Variants. The second stria of the elytra is not con- 

 nected with the marginal at base, is punctiform and broadly 

 interrupted. 



The males may be told from the females by the shape of 

 the anterior fossae and the width of the marginal striae. In the 

 males the fossa has the internal margin sinuate, and the marginal 

 stria broadens suddenly towards the fossae at about its middle. 

 This broadening of the marginal stria causes the male thorax 

 to look less punctate than the female thorax as part of the band 

 of punctures lies in the broadened portion of the stria. Just 

 before the stria enters the fossa it cuts under the edge of the 

 fossa so that a small tooth projects over the stria, thus causing 

 the inside margin of the fossa to appear sinuate. 



Reported to occur in Yucca whipplei (Fall.) and Echinocactus 

 (Blaisdell). 



