74 MEMOIRS OF THE CARNEGIE MUSEUM 
1, opened in 1908 by the writer, many other bones, fragments, and scattered teeth 
of Dinohyus. Some of these fragments were much worn by the elements before 
they were finally deposited, indicating that they were probably transported by a 
Fig. 26. At Work at the North End of Quarry No. 1. (From a photograph by Professor Barbour. ) 
stream of water. When this additional material is used in this paper its catalog 
number is always mentioned in connection with the description. 
GroLoaicaL Notes. 
The lower Miocene of western Nebraska and eastern Wyoming has been sub- 
divided into four horizons. Successively overlying the Oligocene formation these 
horizons are: (1) the Gering beds; (2) the Monroe Creek beds; (8) the lower 
Harrison beds; (4) the upper Harrison beds. The latter horizon is capped at 
Spoon. Butte and other high elevations on the divide between the Niobrara and 
Platte rivers, by a hard stratum of pinkish-gray sandstone (81, p. 28, fig. 1; 72f, p. 
73). This sandstone is from twenty-five to fifty feet (or about seven to. fifteen 
meters) thick. No fossils have been found in this stratum on Spoon Butte by which 
its relative age can be determined. It is perhaps of considerably later origin than 
the Harrison beds, and may even be as late as the Pliocene. For convenience in 
this connection these beds may be called The Spoon Butte beds.” 
It also appears, judging from the fauna of the upper Harrison beds, that this 
89 From a recent publication by Dr. Matthew (Science, N.S., Vol. XXIX, No. 735, p. 196, 1909) it would seem 
that these beds may be regarded as representing the Ogallala formation. 
