ea ee 
166 Cincinnati Soctety of Natural History. 
respect is not so marked as in the specimen before us. In length 
they measure and compare as follows: 
Castoroides. Castor. 
OR ee pi bead ee eee 2.12 mches 1) 2 1.16 inches. 
BD Se Pee ee eae 203 So eee 126225 
Te he ee Se eee 2.30, ° ae 2.00% 2 5 
IN ee eee 400° / Ce Saas 2525 vata 
ISS SS NSE chs Re ee eee 2°95) °) 2S Wa cieacern 
No. I, which supports the homologue of the ‘‘ great toe,” 
which is here the least toe, has the wide, nearly semicircular, pul- 
ley-like groove in the proximal end, which, as in Cas¢or, articulated 
with the internal cuneiform alone. 
No. II, which is comparatively slender, is much enlarged 
at the distal end, where it is somewhat bent inward (toward the 
left foot). It is much flattened laterally at the base, where it 
joined the small middle cuneiform. This flattened proximal end 
is squarely truncated, and has a shallow fossa for the articulating 
surface, and a tubercle on the under side. 
From the markings on either side, it was evidently closely 
packed between the forward and outward process of the middle © 
cuneiform on the one side, and the base of the adjoining meta- 
tarsal‘on the other. No. II reaches both further forward and far- 
ther backward than No. I. 
No. III appears at once to be four or five times stouter than 
No. II. It also bends inward toward the distal end. (This inward 
bending helped to give spread to the toes.) The base, superiorly, 
is broadened and obliquely truncate from within outward and 
backward. ‘The articular surface is concave, vertically. A strong, 
prominent tuberosity extends downward, inward and slightly 
backward, giving the base a twist to the inward, on the under side. 
No. [il must have articulated at the base only with the external 
cuneiform. It will be seen in Castor that No. III extends quite © 
as far, if not a little farther, forward at its distal end than No. IV, 
while here there is quite a perceptible falling short. The back- 
ward slanting base of No. III ends in a spur which laps on to 
a shoulder of the adjacent point of No. IV, giving the latter a 
kind of secondary articular surface on the upper, inner base. 
This feature is more marked than in Castor. The base of No. 
[V (the giant brother of the set) is slightly convex, slants back- 
ward toward the outer margin, and also toward the lower margin. 
