496 TERTIARY INSECTS OF NORTH AMERICA. 



Family ELATERID^E Leach. 

 OXYGONUS LeConte. 



OxYGONUS MORTUUS. 



PI. 5, Figs. 110, 111. 

 Oxygonus mortuus Scudd., Bull. U. S. Geol. Geogr. Surv. Terr., II, 81 (1876). 



The single elytron and its reverse obtained is slender, the humeral 

 angle well rounded, the outer edge apparently a little marginate ; it is 

 almost equal until near the tip, when it tapers to a point. This peculiarity 

 leads me to refer it to Oxygonus, although the apex is not produced so much 

 as in recent species of that group. It is furnished with eight equidistant, 

 rather strongly impressed, but delicate strias, that nearest the suture almost 

 incroaching upon the margin ; these striae are equidistant anteriorly and in 

 the middle, but posteriorly they converge toward each other. 



Length of elytron, 4.55 mm ; breadth, 1.72 mm ; distance of striae apart, 



Q 2mm 



Fossil Canon, White River, Utah. One specimen (W. Denton). 

 CORYMBITES Latreille. 



COEYMBITES VELATUS. 

 CorymUtes velatits Scudd., Bull. U. S. Geol. Geogr. Surv. Terr., II, 81 (1876). 



A single specimen, with its reverse, found. The head and prothorax 

 are gone, but both upper and under surface of the rest of the body, includ- 

 ing the elytra, may be seen in each impression with nearly equal dis- 

 tinctness. The insect appears to have been about the size of C. mediaims 

 (Germ.), but more closely allied in form to C. splendens (Ziegl). The legs 

 have been destroyed, but the middle and hind coxal cavities may be seen. 

 The elytra are of the length of the abdomen, acutely angled, almost pointed 

 at the tip, and furnished, near the outer edge with a broad and shallow fur- 

 row, whose outer limit is abrupt and thus well marked. Besides this the 

 elytra are faintly and distantly striate, with five or six rows of striae, and 

 the mesosternum and metasternum are very delicately granulate. 



Length of fragment, f> mm ; breadth, 3 mm ; distance between anterior 

 edges of middle and hind coxae, 1.75 mm . 



Green River, Wyoming. One specimen, Nos. 137 and 15249 (F. C. 

 A. Richardson). 



