236 The American Naturalist. [Marh 
ON A SMALL COLLECTION OF VERTEBRATE FOS- 
SILS FROM THE LOUP FORK BEDS OF NORTH- 
WESTERN NEBRASKA; WITH NOTE ON THE 
GEOLOGY OF THE REGION. 
By J. B. HATCHER. 
The Princeton Scientific Expedition of 1893, besides secur- 
ing a quite complete series of fossils from the Protoceras beds 
of the upper White River, was also fortunate in securing 
small, but interesting collections from the Loup Fork and 
overlying Equus beds, and in discovering unconformities 
between the latter. These unconformities made it possible to 
distinguish sharply between the top of the Loup Fork and the 
base of the Equus beds; and consequently to separate the fos- 
sils of the one from those of the other with certainty. : 
~ The work in the Loup Fork and Equus beds was done by 
the writer previous to the arrival of the other members of the 
expedition. The material collected was found in the adjacent 
hills on the south side of the Niobrara river, midway between 
the mouths of Pine and Box Butte creeks in Sheridan Co. 
Nebraska. The material from the Loup Fork beds has been 
placed in my hands for description through the kindness of 
Prof. W. B. Scott, under whose direction the expedition was 
undertaken. It contains, besides several species already fully 
described from these beds, the following material representing 
one new genus, and three new species and presenting interest 
ing characters not before noticed in species already known 
AELURODON TAXOIDES, Sp. 0. 
Among the Loup Fork Carnivora, the genus Aclurodon Yi 
predominant, both as to individuals and species a ie 
In size they were propably only equalled among the Me 
ora of this epoch by the sabre-toothed cats. Inthe we 
doubtless found formidable enemies. 
1Curator of Vertebrate Paleontology of Princeton College. 
