34:4: Wortman — Studies of Eocene Mammalia in the 



into an external and an internal portion of which the external 

 is the larger. The office of this notch, which appears to be a 

 part of a foramen, is not altogether clear, but it is a matter of 

 much interest to note that a similar arrangement is seen in 

 the skull of the carnivorous Marsupials. Placed internal to 

 and close to the edge of the fossa is seen the opening of the 

 foramen ovale, much closer in fact than in any species of dog 

 with which I am acquainted. This condition would seem to 

 indicate a narrow brain case, which would be in keeping with 

 the position of the species in the time scale. The position of 

 the foramen is posterior to the fossa as in the Marsupials, and 

 not anterior or opposite to it as in Cynodictis and the 

 modern dogs. Posterior to the glenoid is seen the opening 

 of a rather large postglenoid foramen. 



The lower jaw, figure 2, is relatively a little stouter than that 

 of Cynodictis and considerably more so than that of the fox ; its 

 inferior contour is like that of the typical dogs, being deepest 

 in the region of the inferior sectorial, tapering thence for- 

 wards, and more or less curved posteriorly. The symphysis 

 is short, extending to beneath the anterior border of the 

 premolar as in Cynodictis. In the fox the symphysis is larger 

 and more extended, reaching backward to beneath the anterior 

 border of the third premolar. The angle is broken away in 

 all the specimens of this species in the collection, but the base 

 indicates that it was present and of apparently the same 

 proportions as in Cynodictis. There is an appearance of a 

 slight degree of inflection having been present. The mas- 

 seteric fossa is relatively large and deep, occupying quite one- 

 third the entire length of the jaw ; it has about the same 

 proportions as in Cynodictis but is considerably smaller in the 

 fox. The coronoid is much damaged, but there is evidence of 

 its goodly proportions, both as regards breadth and height. 

 The condyle is somewhat heavier and of greater transverse 

 extent than in either the Miocene or recent genera. 



With the exception of the last superior molar and the superior 

 incisors, the dentition can be fully described. The canines are 

 of moderate size, more or less oval in cross-section at the base, 

 and well pointed. Of the inferior premolars the first is small, 

 single-rooted, with a somewhat conical crown, and separated 

 from the canine and second premolar by short diastemata. 

 The second has a flattened pointed crown, is implanted by two 

 roots, and separated from the tooth in advance by a diastema. 

 The third and fourth are larger two-rooted teeth with laterally 

 compressed conical crowns having distinct anterior and pos- 

 terior basal cusps. The third has in addition to these a faintly 

 marked accessory cusp developed upon the posterior border of 

 the crown. 



