
A Skeleton of Great Fossil Beaver, Castorotdes Ohioensis. 163 
shaft. The homologue of this in Castoroides 1s a thick, heavy 
blade, a process elongated and warped forward at its outer edge, 
where it is thickest. 
Its greatest prominence is nearly opposite the lesser trochanter, 
being much higher up and relatively nearer the great trochanter 
than in Castor. This blade, as it reaches further down, descends 
to the shaft below its middle, and is continuous with a crest that 
meets it from the outer tuberosity below. 
In the form and position of the third trochanter, /7zder is inter- 
mediate between Castor and Castoroides. This femur hasa massive 
look, and its extremities, especially, have a more or less crumpled; 
pitted and spinescent appearance. 
The length of the tibia, between remotest points, is 9.9 inches. 
The fibula, on both the right and left sides, is broken, and the 
lower epiphysis, including the external malleolus, is gone, but its 

: : 
Fie. 25,—One-third natural size. Tibia and fibula: 1, right, anterior view: 2, leit, 
posterior view, upper end down: epiphyses wanting at ¢, e, e; f, fibula: ¢, fibula 
fused with tibia. 
entire length was very nearly 8.75 inches. For 3.75 inches, over 
one-third the length, it is so thoroughly fused with the tibia that in 
