PETERSON : NEW CARNIVORES FROM MIOCENE OF WESTERN NEBRASKA 233 
types’ toward thé recent canids, while the bone on the whole tenaciously retains 
features met with in the early progenitors; viz. the presence of the entepicondylar 
foramen, the heavy deltoid ridge which extends well down on the shaft, and many 
other minor details. 
In comparing the humerus with that of the tiger the similarity is surprisingly 
close, the deltoid crest of the recent form being proportionally even less developed, 
while the distal trochlea is transversely somewhat broader in proportion. The 
Fig. 28. Radius and Ulna of D. superbus. 4 nat. size. 
humerus of Amphicyon major of Europe has also a greater transverse diameter distally 
and the supinator ridge is more rounded and heavier than in the genus under 
description. 
MEASUREMENTS OF HUMERUS. 
Girentestllenigth tiievenss scrsssicuun ocean oc wtew deceedseats 
Antero-posterior diameter of head 
Transverse diameter of head at tuberosities... 44 
Greatest transverse diameter of distal end .. 55 
Greatest transverse diameter of distal trochlea . 34 
Greatest antero-posterior diameter of distal end 
Radius and Ulna (Plate LXXIX).—The radius is proportionally longer and 
the humerus shorter in Daphwnodon than in Daphenus. It is also observed that 
the shaft of the bone in the former genus has a less sinuous curvature than in the 
latter ; in other respects there are only minor details of difference in the two genera, 
and the feline characters are practically as prominently shown in the later as in the 
earlier form, 7. ¢, the inner margin of the head overhangs. the shaft as in 
the cats, the articular surface with the lesser sigmoid cavity of the ulna extends 
well around on the internal side of the head, and the tubercle for the biceps muscle 
is very prominent, while the distal end is quite broad transversely and displays well 
marked tendinal grooves, which, however, are not as well developed as those in the 
tiger. 
The radius in Amphicyon major is also quite cat-like, though the tendinal 
grooves on the inner angle of the distal end are apparently less developed than in 
Dapheenodon. 
™ Wortman, J. L., ‘‘Study of Eocene Mammalia,”’ ete., American Journal of Science, Vols. XI-XIV, p. 348, Fig 
9, p. 488, 1902. 
