SOME EOCENE INSECTS FROM COLORADO AND WYOMING 



By T. D. A. Cockerell, 



Of the University of Colorado, Boulder. 



The insects described below were obtained by or for the United 

 States Geological Survey and are now the property of the United 

 States National Museum. Those from White River, Colorado, and 

 Green River, Wyoming, come from the collection accumulated by 

 S. H. Scudder many years ago. It is generally understood that all 

 these fossils are of Green River age; but they come from different 

 horizons, evidently by no means contemporaneous. It is a matter 

 for the future to minutely study the series of rocks ascribed to the 

 Green River period and determine what subdivisions are necessary. 

 These strata are of peculiar interest at the present time, as they 

 include oil shales, which are expected to prove of great economic 

 importance. 



ORTHOPTERA. 

 Family GRYLLIDAE. 



PRONEMOBIUS ORNATIPES, new species. 



Plate 8, fig. 8. 



Length, 11.5 mm.; width of abdomen, 5.5 mm.; anterior femur, 

 about 2.7 mm.; hind femur, 7 mm.; hind tibia, about, 5.4 mm.; width 

 of hind femur, 2 mm. Anterior femora dark above, but below or 

 posteriorly with a large colorless patch, notched in front and behind, 

 and near the apex with a small spot. Middle femora with the same 

 marks, except that the large spot is almost or quite divided into two 

 elongate ones. Hind femora with oblique stripes as in modern 

 Nemobius, but I can not see any hairs. Each side of abdomen with a 

 series of transverse spots, each connected in the middle with the 

 next, forming a longitudinal moniliform band. Ovipositor appar- 

 ently quite short, exserted about 2.5 mm. 



Eocene. "Cathedral Bluffs south of Little Tommies Draw, at 

 point where samples were taken." (Winchester 17-5; U. S. G. S.) 

 Colorado. Certainly very close to P. tertiarius Scudder, but larger 

 throughout, and probably distinct. Scudder's insect came from the 

 Green River of Wyoming. Scudder does not describe any marking 

 of the anterior and middle femora of his species, but his figure indi- 



Proceedings U. S. National Museum, Vol. 59— No. 2358. 



29 



