529 
THE OSTEOLOGY OF HYiENODON. 
«>nu.wl,a( ,M„re .lender and elongate, but are relatively shorter tl,a„ in most recent 
carnivores. 
^ In the American representatives of the genus there is veiy little 
variation in the structure of the hind-foot. The preceding description is founded 
upon well-preserved si»cimens of no less than four of the species, vis., H. horriim 
//. crucnlus,ll. mmtdinus and H. sp., and the only tangible differences between them 
are Hiose ol siz-e, aside from the few minor variations which have already been 
mentioned, such as the deptli of the astragalar groove, the size and massiveness of 
the various processes for muscular and ligamentous attachments and the like. In 
the small species also (e. g. H. sp. and H. mustelmus) the metapodials are somewhat 
more slender in proportion than those of the larger and more robust forms, but the 
(lifleieiice is not a strikingly obvious one. The agreement with the European spe- 
cies is closer in the pes than in the maims, for in the latter the condition of the 
carpus is (piite dill’ereiit in tlie two groups of species. In the pes the shoi’tness of the 
astragalar neck, the greater prominence of the external, distal ligamentous process 
of tlie calcaneum and the somewhat smaller size of the fibular facet, are almost the 
only divergences to be noted. Schlosser’s figure (No. 5, PI. V, fig. 47) of the hind- 
foot of //. compressus is, it is true, not very like that of the American species in 
appearance, but the dilTerence is, doubtless, partly due to the fact that his speci- 
men is built up from many individuals. Comparing the pes of Oxyatia Patrio- 
fclis with that of Hyceyiodon, the principal difference to be noted consists in the 
shape of the cuboid, its extensive articulation with the astragalus and the conse- 
(juent divergence of the metatarsals, and also the absence of any calcaneo-fibular 
articulation. Hycrnodon has attained the ditfereiitiation of pes which is found in 
the Carnivora, though without any reduction in the number of digits. 
Measurements. 
Pelvis, leiiKtli .... 
Ilium, “ . . . 
“ Kreutest width 
Isehiiiiii, length 
Obturator foramen, fore.and-aft diameter 
Femur, leiif^th (from head) . 
“ lireadtli of iiro.xiinal end . 
“ thickness of distal end 
“ widtli of rotulargnxive 
Tibia, leiiKth .... 
" breadth of jiroxiinal end 
“ “ of distal “ 
Fllmla, length 
“ thickness of proxinial end 
“ “ of distal end 
K . 
c4 
K . 
a c 
P o 
S O 
I ^ 
w 
: 
1 
1 
K 
B 
: B 
K 
i W 
JM. 
0.150 
.089 
.028 
.061 
.0,37 
.165 ; 
.169 
.040 ' 
.041 
.047 
.041 
.044 
.013 
.015 
.133 
.146 { 
.031 
.038 ! 
.038 
.017 
.025 
.018 
.021 
.024 
.123 
.015 
.014 
.017 
.014 
.016 
