THE OSTEOLOGY OF HYiENODON. 507 
and is Idllowcd after a short interval b, the foramen laceram anterius, and this after 
a similar s,,ace, l,j the foramen rotmidnin. These tliree foramina are of neariv the 
same s„,e and are all enclosed in the groove formed by the oblique ridge alL, 
mentioned which runs downward and backward from the postorbital process aemss 
he fron ta , orhito- and allsphenoid. pauddens diffeis from the other species in 
the tact that the foramen lacerum anterius and the foramen ovale are very closely 
approximated and open almost side by side. The foramen ovale is separated by a 
wide interval, both from the foramen rotundum and from its fellow of the opposite 
side. Tliere is no alisphenoid canal in any of the American species. The foramen 
lacerum medium and foramen lacerum posterius are situated much as in the dogs, at 
the front and hind edges of the tympanic bulla; the carotid canal appears to be 
fused with the latter; at all events, I have seen no specimen in which it is distinct. 
The cimdylar foramen perforates the basioccipital well in front of the condyle. The 
postglenoid foramen is distinct, as is also the stylo-mastoid, and the supraoccipital 
is perf'orated by two venous forfimina. The posterior palatine foramina perforate 
the palatines, in each of which are three openings, a larger one which opens near 
the ina.xillary suture, and behind it two much smaller ones, just such as Schlosser 
has described in the European species: “Die Gauraenbeine weisen zwei grtissere 
Durchbriiclie auf, dahinter noch je z.wei kleinere Foramen” (No. 5, p. 175). The 
infraorbital foramen is a high, narrow oval, and placed above P^. According to 
Filhol (No. l,p. 19) there are some important difiereiices in the arrangement of the 
cranial foramina found in the European species, at \Q'\s,i\\\ H. bracJiyrhy7ichus,{mm 
that above described. The foramen lacerum posterius is distinct from the carotid 
canal and perforates the basioccipital, and an alisphenoid canal is present. These 
are tlie most significant differences regarding the foramina between the species of 
the (lid and New AVorlds. 
Measure.wents. 
Skull, leiigtli from occipital condyles to Incisive alveolus 
“ “ from for. mag. to front of orbit 
“ “ of face from orbit to incisive alveolus 
“ breadth across zygomatic arches 
“ length of sagittal crest . . • • 
“ height of occiput . . . • ■ 
“ breadth of weiput at mastoid processes . 
Mandible, length from condyle . . • • 
“ height of coroiioid jirocess 
“ ‘‘of condyle . . • ■ 
“ depth at “8 . • • ■ ' 
“ “ at P2 . . • • • 
w 
M 
H. HORRIDUS, 1 
No. 1. 1 
D 
5 . 
P 
w 
D 
. 
P 
w 
< 
p 
s 
w 
H. PAUCIDENS. 
M. 
L , „ 
0.209 
0.290 
' 0.310 
0.232 
0.172 
0.170 
.121 
.144 
.172 
.130 
.114 
.101 
.092 
.140 
.143 
.108 
.067 
.073 
.114 
.140 
.072 
.103 
.117 
.091 
.077 
.071 
?.060 
.067 
.064 
.100 
.079 
.054 
!i66 
.270 
.280 
.203 i 
.148 
.1.33 
.058 
.077 
.060 
.054 
.047 
.028 
.030 1 
.050 
.034 , 
.020 
.022 
.042 
.055 
.038 ‘ 
.027 
.025 
.037 
,056 
.028 
.021 
& 
% 
.055 
.017 
.015 
66 JOURN. A. N. S. PHILA., VOL. IX. 
