AMERICAN COLEOPTERA. 141 



bearing a few hairs at the sides; elytra uniformly coarsely punctate, 

 not granulate, very plainly dilated a little in front of the middle in 

 the female. Beneath, the palpi, flanks of thorax, legs and sides of 

 abdomen are moderately hairy. 



This species is confined, as far as I know, to the shores of Lake 

 Como in Wyoming, where it runs on bare alkaline mud. My speci- 

 mens were taken by Mr. Knaus in June, 1901, he having purposely 

 gone to the locality whence came the type specimens. The speci- 

 mens in the LeConte collection would favor the union of this species 

 with fulgida in some respects, but the form of the female elytra is 

 alone sufficient to differentiate it. 



C pseudosenilis Walther Horn, 1900, Ent. Nach., xxvi, p. 117. 

 Length 13-14 mm. ^.52-. 56 inch. 



Habitat. — Owen's Lake, Inyo Co., Cal. 



Green bronze; beneath, bluish green, elytra almost black, with 

 markings broad, consisting of humeral lunule, middle band and 

 apical lunule shaped as in the preceding, but not connected at mar- 

 gin. Head not hairy in front, otherwise as in the preceding; head 

 and thorax also as in the preceding. Beneath, scarcely hairy, the 

 few hairs being confined to the palpi, flanks of thorax and femora. 



This species is often erroneously placed under the name senilis, 

 with which it has no close relationship. It might be regarded as a 

 variety of Willistoni, but in view of the differences in marking, in 

 hairiness and in locality, I consider them as distinct species, each 

 confined to a very limited area. It is possible that intermediate 

 forms may be found at other alkaline lakes in the west. 



Senilis group. 



Thorax convex, not margined, subquadrate; palpi ^ pale at base; elytra convex, 

 markings broad, not connected at margin ; elytra punctate, more finely 

 towards apex, not granulate, apices not serrulate; interocular strise 

 fine, numerous, reaching nearly to the labrum ; front slightly hairy ; 

 last ventral % symmetrically emarginate senilis. 



€. senilis Horn, 1866, Proc. Ac. Phil., p. 395; Schaupp, I.e., p. 92, pi. 3, fig. 61. 

 (This figure does not accurately represent the middle band.) 

 Length 12 mm, =.48 inch. 



Habitat. — California, west of Sierra Nevada ; Alameda Co. 

 Black, opaque, beneath green ; elytral markings consist of humeral 

 lunule, middle band, entering perpendicularly and arcuately bent 



TRANS. AM. KNT. SOC, XXVIII, MAY, 1902. 



