1 899-1 Matthew, Fresh- Water Tertiary of the West. 65 



IX. LOUP FORK. 



The localities tabulated below are as follows : 



1. Northeastern Colorado. Headwaters of Cedar, Horsetail, and 

 Pawnee Creeks, in Logan and Weld counties, north of the South 

 Platte River. Sands and gravels overlying the White River clays, 

 usually unconformably with heavy conglomerates at or near the 

 base. Another unconformity of erosion occurs sometimes within 

 the formation dividing it into horizons D and E (p. 23) ; but no 

 important faunal distinctions appear. These unconformities of 

 erosion in fluviatile beds are not of much importance. Collec- 

 tions made by Prof. Cope in 1S73 and 1879, and Amer. Mus. 

 Exped. of 1898. 



2. Laramie Peak, Wyoming. A small collection chiefly of 

 Merychyus, made for Prof. Cope in 1880. 



3. Deep River, Montana. A limited area in the valley of Deep 

 Creek or Smith River, near Great Falls. Collections made for 

 Prof. Cope in 1877, and Princeton Expedition of 1892. 



4. Cottonwood, Oregon. Cottonwood Creek in the valley of the 

 John Day River. Collection made for Prof. Cope in 1879 by Dr. 

 J. L. Wortman. 



5. Oregon Desert. See foot-note, p. 70. 



6. Ah'braska. In the basins of the Loup River (Loup Fork) 

 and Niobrara River, and elsewhere in the central and northern 

 part of western Nebraska. The fauna, described mainly by 

 Leidy and Marsh, is the typical and largest Loup Fork fauna. 



7. N'eio Mexieo. This fauna was described by Cope in 1874 

 from the collections made by the Wheeler Survey, and now pre- 

 served in the National Museum. Most of the species came from 

 the Santa Fe basin. 



8. Kansas-Nebraska. Northwestern Kansas and southwestern 

 Nebraska in the drainage basin of the Republican River. The 

 latest of the Loup Fork faunas, some of it Pliocene according 

 to Prof. Scott. The short-legged Rhinoceroses are the most 

 abundant fossil. 



9. Texas. In northern Texas, near the head of the Red River, 

 along the northeastern border of the Llano Estacado. 



