40 TEETIARY COLEOPTERA OF NORTH AMERICA. 



margiiiate, the surface with the same sculpturing as the prothorax, and 

 besides very faintly and very narrowly striate with long-itudinal punctures, 

 or more properh* stria?. These are about as distinct as in T. striolatus LeC, 

 but are whollv different on account of their extreme slenderness and the 

 longitudinal character of their components. 



Length of body as preserved, 9.25 mm.; length to tip of elytra, 8.1 mm.; 

 breadth, 4 mm.; length of elytra, 4.6 mm. 



Florissant, Colorado; one specimen. No. 9210. 



Tropisternus limitatus sp. nov. 

 PI. V. %. 2. 



Although this species is placed in this genus, it is only temporarily, 

 until better and more abundant material shall give the opportunity of 

 properly characterizing the genus to which it really should be referred, 

 which, so far as we know, is extinct. It belongs without doubt to the 

 Hydrophilini, as its wide prothorax and compressed tarsi show, but as the 

 genera of Hydrophilidse are tolerably constant in size and this is very 

 much smaller than any Hydrophilini known, it can hardh' be doubted that 

 it will prove a distinct generic ty23e ; moreover the structure of the hind 

 tarsi is very different from what we find in the other genera ; for though 

 strongly compressed, they are subequal, somewhat ovate, and two or three 

 times as long as broad. The whole insect is of a very regularly elongate 

 oval shape, of a uniform carbonaceous color, showing no sculpture what- 

 ever beyond a pair of straight raised lines, converging posteriorly, which 

 cross the prothorax and thiis limit a wedge-shaped median piece, the front 

 margin of which is rather more than one-third of the front border of the 

 prothorax, while the hind margin is about one-third its anterior width. It 

 is probable, however, that these raised lines are indications of some scul])- 

 tural charactei'istics of the iinder surface, as they are not quite symmetrical 

 and do not appear on both specimens referred to this species. The eyes 

 are large, subglobose, extend slightly beyond the curve of the head, and, 

 as viewed from above, are longer than broad. The sutural edge of the 

 elytra is very delicately margined. 



Length, 5 mm.; breadth, 2.6 mm. 



Florissant, Colorado; two specimens, Nos. 2956, 3179. 



