190 COPE. [Vot. III. 
in certain Edentata; and crests on the extremity of the radius 
are adaptations to the carpal bones. 
The tongues proper are all imperfect in the Rodentia and 
Carnivora (Figs. 5, 6) (except the Leporidz, which are especially 
characterized by their great speed). Among Ungulates they are 
very imperfect in the Proboscidea. The orders mentioned all 
have elastic pads on the under sides of 
their feet or toes. The same is true of 
the lowest types of both the Artiodactyla 
and Perissodactyla, the hippopotami and 
rhinoceroses. In the Ruminantia the troch- 
leze are well developed (Fig. 37) with one 
exception, and that is the distal metacarpal 
and metatarsal keels of the Camelide (Fig. 
Fic. 29. Fic. 30. Fic. 31. Fic. 32. 
Figure 29. — Distal extremity of tibia of Amdlyctonus sinosus Cope. 
Figure 30. — Distal extremity of tibia of Oxyena morsitans Cope. Both creodont 
flesheaters and two-thirds nat. size; from Report Expl. and Surv. W. of rooth Mer., 
G. M. Wheeler, IV., Pt. II. 
Figure 31. — End of tibia and astragalus of Archelurus debilis. 
Figure 32.— Femur of Mimravus gomphodus. Both carnivores. One-third nat. 
size; Mus. Cope. 
36). These animals confirm the probability of the completion 
of the keels being the effect of long-continued shocks, for they 
are the only Ruminants which have elastic pads on the inferior 
sides of their digits. 
That these processes may be displacements due to shocks 
long continued is rendered probable by the structure of the 
