1881.] "J^OO [Cope. 



fossa. Its internal extremity is broken off. Posterior to, and in contact 

 with it, the posterior cingulum rises in a crest, which occupies the internal 

 half only of the border. Its inner border is imperfect. It appears to me 

 to be probable that the normal posterior crest is turned posteriorly on itself 

 so as to give the "pot hook " shape seen in the anterior crest of the fourth 

 permanent premolar. The corresponding accessory crest in the fourth 

 temporary premolar appears to have been distinct at its internal extremity. 

 The second true molar has a more oblique posterior external crest, and the 

 posterior internal is oblique and simple. It has narrow anterior and pos- 

 terior basal cingula. There is no tubercle between the inner bases of the 

 transverse crests of this or the last true molar. The latter is characterized 

 by the rudimental character of the posterior external crescent crest, which 

 is shortened like that of Hyrachyus. The transverse crests are curved 

 backwards ; the posterior is short and simple. 



The canines are small, and are directed forwards. The extremity of the 

 muzzle being broken, the relation of the incisors cannot be stated, but 

 there was not probably any precanine diastema. An incisor preserved has 

 the crown transversely expanded, and rather oblique. 



The third and fourth inferior premolars are the deciduous ones, and are 

 both three-lobed, but differ in the forms of the anterior lobe. In the third, 

 it is narrow and incurved, as in the corresponding permanent teeth of some 

 Artiodactyla. The transverse crests of the true molars are rather oblique, 

 running forwards as well as outwards. 



Their external extremities are bent at right angles, and there results a 

 short descending crest running forwards and inwards ; the anterior one 

 turns inwards, again forming a transverse anterior ledge. No cingula on 

 internal or external bases of crown ; a rudimental posterior one. 



Measurements of Cranium. M. 



Length from front of canine tooth to end of occipital 



condyles 128 



Length from same to postglenoid process 096 



" " " to end of last molar 069 



" " " to first premolar 015 



" " " to line of front of orbit 044 



Width between superciliary borders 046 



" of zygomata at orbits 064 



" of brain-case at glenoid surface 048 



" of occipital condyles 023 



" of basioccipital bone between ossa petrosa 006 



Distance between postglenoid and posttympanic pro- 

 cesses 014 



Depth of occiput behind , 033 



" of mandible from condyle 040 



" of mandibular ramus at third premolar 014 



'* at diastema (axial) 009 



Least width of symphysis Oil 



