1884.) 525 ' [Cope 
crania of the Ma superbus, where both are well preserved and exposed, the 
bulla is considerably more prominent than the postglenoid process. The 
glenoid surface is well-defined and equally wide at both extremities. The 
inferiorly: presented surface of the zygomatic arch, is wider than in any of 
the other species, including examples of JZ, superbus of superior dimensions 
in other respects.. The surface is rugose. The length from a line connect- 
ing the median external columns of the last superior molar, to the poste- 
rior nareal border, enters three.times into the distance from the latter to 
the border of. the foramen magnum. In JM. superbus it goes three to three 
anda half times; in J macrostegus and M. montanus once only. Be- 
inind the molars the produced palatal roof is more, concave than between 
the last two true molars. The palate becomes then more concave (convex), 
and between the first premolars and canines ‘becomes flat, and expands 
laterally. The nareal fissure is not much contracted between the pre- 
maxilliaries. 
The infraorbital foramen is above the anterior half of the superior fourth 
premolar, and is of moderate size. The frontal foramina are separated by 
a space which is less than half as wide as that which separates each one 
from the superciliary border. There is no supraorbital notch. The in- 
cisive foramina are large, are wider than long, and approach close to the 
bases of the canine teeth. The palatine foramina are minute or obsolete: 
The foramen ovale is isolated and is opposite the junction of the glenoid 
and postglenoid surfaces. The jugular foramen is isolated by the exten: 
sive contact of the otic bulla and the basicranial axis. Perhaps the 
condyloid foramen is included in it, as I do not find it in the usual position. 
The animal is so old that no sutures are visible. 
The teeth are not all cleared from the matrix, which is hard and brittle, 
The first true molaris much worn. The first premolar is two-rooted, and 
ig separated from the canine by a diastema equal in length to the long dia- 
meter of its crown. 
Measurements. M. 
Length from occipital condyle to front of canine tooth. B00 
y vy yy fe ‘« postglenoid process... .041 
uf i ‘i wee « yostfrontal process. .. .1382 
B NY i Hf ‘« palatonareal border .. .118 
af st if WN «end of last molar..... .146 
Diaiierare oprorbice VOTPICAT: isisrasaueneie nis Waieauewe manne dys doses ROE 
. (transverse ...... Pee enna hare «O89 
Depth of malar bone at middle of orbit, .....-.+-- whe yen oe 
«  « zygomatic process to glenoid face behind,.... .088 
Width of top of muzzle at preorbital fossa ....+..+..++ .048 
‘at middle of supraorbital border.,..++++.-..++++ O94 
ce © malar. below Orbit. 0... ese eeeeer erence nee eens 160 
«© middle of zygomatic arch. ..sseeeee renee eres 254 
‘© of occiput at superior crests. .....esee cere ress 050 
