480 THE STRUCTURE AND RELATIONSHIPS OF ANCODUS. 
Kow»lev*/8 ngure (No. 8, PI. XXXVII. fig. 20) the two media,. ..mtacarpals 
(III and IV) a, -e shown » being of the same length, and n,c. IV ,s much the more 
AnJcr of the two. Whether this joroportion really characterizes the Lui-opean 
simchnens, or is due to the association of bones from different 
same inanns, cannot well be determined. Filliols figure (No. 1, PI. 24, fig. 116) 
would favor the latter conclusion. , i i j 
The fourth metacarpal is somewhat wider and markedly shorter than the third. 
The head bears a nearly plane fecet, of subtriangular shape, for the unciform, which 
extends somewhat farther back upon the posterior projection than m Oreodon, and 
the depression on the ulnar side for the head of me. V is rather more deeply marked 
than in that genus. The lateral hicets for the.adjoining metacarpals are large and 
Hat. The shaft is somewhat more compressed in the fore-and-aft direction than 
that of me. Ill, but is otherwise like it, as is also the distal trochlea. 
The fifth metacarpal is shorter than the second, and is consequently the shortest 
of the series, except me. I. It is somewhat heavier in proportion, but otherwise 
almost exactly like the corresponding bone in Oreodon. The head is quite rugose 
and heavy, and carries a narrow, oblique, and saddle-shaped facet for the unciform. 
The articular surface for me. IV on the radial side of the head is broad in front, 
becoming very narrow toward the palmar side. The shaft is stout and of trihedral 
shape, broadening regularly to the distal end. The figures of Kowalevsky and 
Filhol show this bone of (juite a different shape in the Ronzon species; it is longer 
and straighter, with a less expanded and rugose head, and is less distinctly enlarged 
at the distal end. Filhol’s figure appears to indicate the extension of the distal 
Carina farther upon the dorsal face of the trochlea than occurs in the American 
species. 
pJialanges oi the pes are much better represented in the collection than 
those of the manus. It will suffice for the present, therefore, to note a difference 
which obtains between the proximal phalanges of the fore and hind feet. In the 
manus the first ^^halanx has a subcircular proximal end, with shallow concave 
facet for the metacarpal, notched on the palmar border for the carina. The shaft 
is nearly straight, its distal portion becoming wide and much compressed in the 
dorso-palmar direction. The distal trochlea is very low, very obscurely divided in 
the median line, and not reflected upon the dorsal side of the bone. The lateral 
processes for ligamentous attachments are inconspicuous. 
V. THE HIND LIMB. 
The/./m is not represented in the collection at all, except by some fragments 
which show that the ilium was quite broad and probably like that of Oreodon. 
f 8) only the distal portion is preserved in the spe- 
cimen of A. brachyrhymehus; it indicates a much larger and more massive bone than 
Surface fri i " is heavy and trihedral in shape. The 
form a deen n't ° Pi^^haris muscle is large and rugose, but does not 
form a deep pit or depression, as is the case in the European species. The rotular 
