PETERSON: A REVISION OF THE ENTELODONTIDA 129 
heavier, and also considerably shorter, than in the Princeton specimen. The head 
is well rounded ; it is set on a distinct neck, and the depression for the ligamentum 
teres is rather small and shallow. The lesser trochanter is quite large, and projects, 
as in the Oligocene genus, almost entirely backward.“ Between the greater and 
lesser trochanters is a ridge extending obliquely across the posterior face of the shaft 
which is more prominent in the present 
genus than in Archeotheriwm. Immediately 
in front and superior to the lesser trochanter 
is a prominent and very rugose ridge, which 
runs parallel with the shaft and is separated 
from it by a deep groove. The middle re- 
gion of the shaft is proportionally less con- 
stricted than in Archxotheriwm and the linea 
aspera is more developed than in the latter 
genus, a character which agrees better with 
what we know of Bodchwrus through Cope 
(10, p. 65). The large and rugose groove 
above the external condyle, for the plantaris 
muscle, terminates above in a heavy and 
very rugose tubercle; immediately above 
c=) ? 
the internal condyle on the posterior angle 
there is a prominent ridge for muscular 
attachment. The shaft of the femur as a 
whole is more arched than in the Princeton 
specimen. The rotular trochlea is short, not 
very deep, but broad, and slightly oblique. 
The condyles are rather small, the external 
Fia. 75. Internal and Anterior Views of Femur of 
being the larger of the two, and placed Type of D. hollandi Peterson. } nat. size. 
more directly fore-and-aft than the internal. 
The intercondylar fossa is deep, oblique, and wider in front than behind. 
One of the more important differences between Dinohyus and Boécherus humer- 
osus is revealed in the comparative diameter of the distal end of the femur. In Di- 
nohyus the femur has the antero-posterior diameter proportionately greater than in 
Archeotherium ingens, and in this respect Dinohyus more nearly resembles Hippo- 
potamus, while, in Bodchwrus humerosus the diameter of the distal end is more nearly 
* Cope states (Bull. U. 8. Geol. Surv., Vol. V, p. 65, 1880) that the lesser ‘‘ trochanter is large and projects well 
inwards.’’ 
