382 BULLETIN 63, UNITED STATES NATIONAI^ MUSEUM. 



marginal groove well dev^eloped beneath the slightly expanded ex- 

 ternal border of the dorsal plate and terminating at the fossa beneath 

 the angle. Internal margins of the Aalvcs contiguous in basal two- 

 thirds; fissnre narrowh^ fusiform in apical third, and the inferior 

 pudendal membrane is not visible. 



Ilahitdt. — California. Forma si/blaevis, about San Francisco Bay: 

 Forma ti/pica^ central California, along the coast; San Joaquin and 

 Sacramento valleys; Calaveras County; Tulare County, Ralph Hop- 

 l^ing; Los Angeles County, Doctor Van Dyke; Forma intermedia., 

 northern California, southern Oregon, western slopes of the Sierra 

 Xevada Mountains. 



Professor Wickham in his " Coleoptera of Colorado " says that 

 Professor Snow has reported one specimen from Colorado. It is in 

 all probability a variation of pimelioides. 



Number of s})ecimens studied, 500. 



Type in the Eschscholtz collection? 



r?//>e-7orY/7%.—" California." 



Salient t^jpe-charaeters. — Ovate, robust, shining-. Head and pro- 

 notum coarsely and coiiHiiently punctate; thorax siibcordate, apex 

 feebly emarginate, angles ()l)tuse; sides more strongly rounded in 

 front, narrowing rather suddenly behind the middle, causing them to 

 appear somewhat angulate; strongly constricted at base; angles 

 rectangular. Elytra oval; humeri much rounded and obtuse; disc 

 arcuately and vertically declivous posteriorly; surface densely and 

 rugosely muricato-tuberculate, less strongly so along the suture. 



Dia(j)iostic cliaraeters. — Cordata diifers from all other species in 

 the subgenus Blapylh^ except pimelioides^ in having the sides of the 

 prothorax more or less subangulate. This character is especially 

 marked in the males. The prothorax is more evenh^ rounded behind 

 the middle in most females, but always strongly constricted at base. 

 giving it with the above characters a subcordate appearance. The 

 marginal bead does not reach the base. 



The coarse sculpturing will cause it to be frequently confused Avilli 

 scahrom^ but the setose propleura' of the latter Avill readily separate 

 the two, besides the pronotal sculi)turing is quite different in the 

 two species. Claricorvi.s is much less strongly sculptured, and the 

 sides of the i)r()n()t!il disc are distinctly setose along, with the pro- 

 pleurjp. 



In pimcUoidcs and hninnipes the elytra are sculptured with rows 

 of small and rounded tubercles; in the latter species the legs are 

 brown oi- i-eddish. 



In studying a large series of cordata it is very evident that the 

 sculpturing varies toward pimelioides, so that in the heterotypes it is 

 quite difficult to tell where one species leaves off and the other begins: 



