1896. ] NEW YORK ACADEMY OF SCIENCES. 253 
1873, however, the investigations begun by Leidy, Marsh and 
Cope in the Tertiary lake basins, which form so prominent a 
feature in the geology of the western interior, revealed the 
presence of vertebrate fossils on the American continent. <A 
further study of these fossils showed them to be of great scien- 
tific value, and many paleontologists turned their attention to 
their collection and study. This gave a great impetus to the 
science of vertebrate paleontology, and led to the discoveries 
of Cope, Marsh, Osborn, Scott, Wortman and many others, at 
the same time resulting in a thorough and exhaustive study of 
the faunal relations and geology of the various members of the 
western Tertiary. The White River Miocene of South Dakota, 
the John Day beds of Oregon, the Deep River beds of Montana, 
the Bridger and Washakie basins of southern Wyoming, the 
Uintah beds of Utah—all these were thoroughly searched and 
explored by the fossil gatherers. No Tertiary was left unex- 
plored, and paleontologists were eager to find fresh fields for 
discovery. It was thus natural that their attention should be 
attracted by a series of shales situated in northern Utah, at the 
eastern extremity of the Uintah Mountains, a formation that 
had been for a long time known to geologists, but one which 
they had not as yet been able to identify. I refer to the beds 
known under the name of Brown’s Park. A thorough search of 
these beds was then made, for it was thought that, as they were 
of an entirely different nature from any Tertiary in the region, 
such vertebrate remains as might be there discovered would 
prove to be of great scientific value. 
The result was—and it is this fact perhaps that has been the 
cause of the many conflicting opinions concerning the beds— 
that as a source of vertebrate fossils the Brown’s Park was an 
absolute failure. The formation is throughout entirely barren. 
Not only have the bones of mammals not yet been discovered, 
but, with the exception of a few moilusca, not even an inverte- 
brate. 
As a geological question, however, in proportion as their bar- 
renness has become more evident, the interest in the beds has 
increased, and it is the purpose of this paper to set forth a few 
of the more important facts connected with them. 
Geographically considered the formation is situated in north- 
eastern Utah at the eastern extremity of the Uintah Mountains. 
The Green River which is the great drainage factor of this part 
of the country flows south through southern Wyoming, cuts 
into the edge of the Uintah fold and takes a sharp bend to the 
east. It pursues this easterly course for some 50 miles, and 
finally sweeps around to the south again, crosses the axis of the 
