The American Geologist. 
May, 1896 
280 
chambers, but if so the posterior one is not ossified, and the 
periotic is exposed. Genus has dentition like the dog. with 
limbs more like the bear. 
Dr. Scott (No. 5, p. 211) says, ‘-The White River dogs with 
three upper molars are quite different from the true Amphicy- 
cns (No. 3, p. 219) and for these the name originally given 
them by Leidy, Daphcenus , should be revived.” 
Temnocyon resembles the White River Daphcenus in many 
respects, as will be seen later on. and differs in not having a 
third superior true molar; in the trenchant talon of mTi ; the 
absence of internal cusps on mT 2 and in having very much less 
expanded zygomas. Other characteristic features of Daphce¬ 
nus cannot be compared with Temnocyon on account of the 
poor preservation of these parts in the latter genus. In all 
ca?es the species used for comparison is Cope’s D. (Canis ga- 
lecynus) hartshornianus. 
Temnocyon exhibits a very much more elongated and rela¬ 
tively more compressed skull than the White River genus. 
This is best illustrated by the following: The length of T. 
ferox from the line of the least diameter of the frontal to the 
posterior crest of the supra-occipital is 111 mm., and in Daphce¬ 
nus 72 mm. The greatest width of the parietal in the former is 
70 mm. and in the latter 45 mm. From the parietal to the nasal 
the diameters are considerably less diminished than in Da¬ 
phcenus ■, and the molar, as might be expected, is more promi¬ 
nent in this latter species. The parietal is considerably more 
rounded in T. ferox ; the crest of the supra-occipital is much 
narrowed and compressed and is carried high above the pari¬ 
etal, forming a narrow" elongated ridge, this being due in a 
great measure to the greater rounded backward and down¬ 
ward curve of the parietal. 
In p. i the external edge of the Crown inclines inward and 
forward and the entire form is essentially like that of the 
type of Temnocyon. The development of the cones is propor¬ 
tionately greater in the larger species, there is, how r ever, a 
compression at the anterior edge between the proto- and deu- 
terocones, wdiich is not present in the type nor in T. wallovi- 
a-nus-, but is developed in T. ferox and in T.joseplii. The 
deuterocone (which in T. ferox is posterior) is in both Da¬ 
phcenus and T. altige 1 iis anterior to the centre, and hence the 
