386 NOTES ON THE CANIDZ OF THE WHITE RIVER OLIGOCENE. 
The unciform facet is large and plane and does not rise so high upon the head as in the 
modern genus. On the radial side we find no distinct facet for the trapezoid, which, as 
already mentioned, thins to a mere edge toward the magnum, but there is a well-defined 
facet for the projection fromthe head of the second metacarpal, which is proportionately 
larger than in Canis. On the distal end of the magnum is a narrow facet for the third 
metacarpal, a facet which is less concave in the dorso-palmar direction than in the case 
of the last-named genus. 
The wneiform is viverrine rather than canine in character, being much narrower 
in proportion to its vertical height than in the recent dogs. The facet for the seapho- 
lunar, which in Canis has an almost entirely proximal position, is in Cynodictis much 
more nearly lateral. The pyramidal facet is also decidedly more steeply inclined than 
in the existing genus, the two articular surfaces meeting at a very acute angle and mak- 
ing the proximal end of the unciform narrow and wedge-shaped. On _the radial side is 
a large facet for the magnum and a small one, confluent with it, for the extension from 
the head of the third metacarpal. The distal facets, for the fourth and fifth metacarpals 
respectively, are narrower than in Canis, contracting especially toward the palmar side. 
The metacarpals, five in number, are remarkably short, slender and weak and.haye 
but little resemblance to those of the recent dogs. 
The first metacarpal is very small, but is, nevertheless, proportionately much less 
reduced than in Canis, taking the length of me iii in each genus as a standard of 
comparison. The head is thicker and relatively heavier than in Canis and on the radial 
side, internal to the trapezium facet, is a tubercle for the attachment of the lateral liga- 
ment. The facet itself is much less deeply concave transversely than in Canis, but 
more convex in the dorso-palmar direction. The shaft is short, slender, arched toward 
the dorsal side, antero-posteriorly compressed and of oval section, tapering considerably 
toward the distal end. The distal trochlea is very small, but formed entirely like those 
of the other metacarpals ; it is strongly convex, almost hemispherical and bears a dis- 
tinct carina upon the palmar face, just as in Daphenus. In Canis, on the other hand, 
this structure is of an entirely different character, forming an asymmetrical hemicy- 
linder, with a broad shallow groove placed somewhat internal to the median line, and 
thus resembles the trochlea of a phalanx rather than that of the other metacarpals. 
The second metacarpal is represented in the collection only by a single imperfect 
Specimen, consisting of the proximal end. This shows a much stouter shaft than me i, 
being of about the same diameter as the corresponding portion of me iy, and more slen- 
der than that of me iii. The head is narrow and bears a saddle-shaped facet for the 
trapezoid, but sends out a projection which rises more above the head of me iii than in 
Canis and articulates with the magnum by a larger facet than in that genus. 
