404 TERTIARY IXSECTS OF NORTH AMERICA. 



emargiiiate ; a slight median sulcation, but scarcely any sign of a depres- 

 sion at the apex. Surface nearly smooth, but coarsely, distantly, and 

 faintly punctate. Corium of heraelytra clear. 



Length, 5 2.5™"; breadth, 2.1°"". 



Florissant. One specimen. No. 6390. 



3. LiTHOCHKOMUS MORTUARIUS. 



PI. 26, Fig. 2. 



Antenna slightly longer than head and thorax together. Thorax sub- 

 quadrangular, less than half as broad again as long, less than half as long 

 again as the head, and only as long as the width of the head, broadest 

 before the base, with rather strongly convex sides, tapering only in the 

 apical half, but rapidly; the apex three-fourths the length of the base; a dis- 

 tinct posterior lobe not one-fourth the length of the anterior; the front mar- 

 gin transverse or very slightly emarginate, with a distinct triangular ante- 

 rior depression, twice as broad as long, the apex broadly rounded ; surface 

 indistinctly punctate. Corium of hemelytra blackish fuscous ; membrane 

 with slight marks of longitudinal infuscation. 



Length, 4.6°"° ; breadth of base of thorax, 1.85"°" ; abdomen, 2.25"°'. 



Florissant. Two specimens, Nos. 4644, 11220. 



4. LiTHOCHROMUS EXTRANEUS. 



PI. 26, Fig. 6. 



The single specimen is preserved only upon a side view, and is on that 

 account difficult to compare with the others absolutely. The head appears 

 to be of unusual length, being apparently about five-sixtlis the length of the 

 thorax, and is smooth ; the antennae are exceptionally stout and are some- 

 what longer than the head and thorax together ; the first two joints together 

 slightly shorter than the last two ; the first and second joints increase very 

 slightly in size next the apex, and are truncate at tip ; the last joint scarcely 

 enlarges toward the tip, which is rounded. Thorax apparently tapering 

 from a little before the base, somewhat tumid, and punctate ; corium of 

 hemelytra clear, or very slightly obscured, punctate throughout, but more 

 densely along the principal veins ; membrane clear. 



Length, 5.5""; of corium of hemelytra, 2.75"°'. 



Florissant. One specimen, No. 13660. 



