70 BT'LLETTN 03, IGNITED STATES NATIONAL MUSEI'M. 



Habitat. — XeAv ^Mexico (Cloudcroft. James Canyon, June, Warren 

 Knaus) . 



Number of specimens studied, 8. 



Sexityj^es in my OAvn collection. 



Type-locality. — Cloudcroft, New Mexico. 



Collector. Warren Knaus. 



Salient type-characters. — More or less shining, estriate and moder- 

 ately convex. Pronotum subquadrate; disc rather finely, irregularly 

 and sparsely punctate, punctures denser at the sides ; apex very feebly 

 emarginate ; apical angles distinct and not at all prominent ante- 

 riorly; basal angles obtuse. 



Elytra with the humeri more or less exposed; disc almost coarsely, 

 irregularly, and rather densely punctate, punctures subequal in size 

 and obsoletely subnuiricate; laterally denser, with a slight tendency 

 to rugulosity. Legs rather short and somewhat slender. 



Diagnostic characters. — Reseml:)les the robust form of extricata or 

 nleyi in general outline. If it inhabited the region where parvicollis 

 is found it might be mistaken for that s})ecies ; some forms of lecontei 

 resemble it. First of all, the genital characters distinguish it from 

 all the above and associates it with ohsolcta which it resembles, but 

 less strongly in general habitus. It is usually confounded with 

 extricata^ from which it differs in the mutic anterior femora of the 

 male, the more strongly arcuate sides of the pronotum at anterior 

 two-fourths, and besides the punctuation is (juite different. 



In rileyi the female has the anterior spurs of the anterior tibitie 

 strongly developed, Avhile in knaasii they are but feebly broadened. 

 The spurs have greater development in the male of rileyi also than 

 in the male of l-nausii. 



In parrieolVts and lecontei the lateral margins of the pronotum is 

 distinctly visible from above, while in knansii the pronotal sides are 

 arcuately declivous. The genital and tarsal charactei-s are also dis- 

 tinctive. 



h'naiis'd ditfers from tA'pical ohsoleta in its smooth and shining sur- 

 face and estriate elytra. It is also more robustly ovate than in the 

 smooth form of ohsoleta. 



I am indebted to Mr. Warren Knaus foi- this interesting species, 

 and I take i)leasure in dedicating it to him. 



Knaiisii appears to l)ear the same relation to the Carhonaria section 

 that rileyi bears to the (Jiatd ricoUi.s section. In this respect the two 

 species are analogous. 



There is a specimen belV)re me from Cananea, District of Arizpe, 

 State of Sonora, Mexico, that resembles knausii in form, but it is more 

 alutaceous and smoother, the striiv of punctures are more evident and 

 the interstitial punctures smaller and less conspicuous. The anterior 

 tibial spurs are also feebly developed, and while the study of the 



