NOTES ON THE CANIDZ OF THE WHITE RIVER OLIGOCENE. 369 
slightly concave transversely, but has a low median conyexity, with very feebly devel- 
oped keel, the convexity being much less prominent than in Daphenus. 
The exoceipitals are low and wide and so conyex in the median line that this por- 
tion projects much behind the sides. The condyles are low and depressed and are 
separated on the ventral side by a narrower, deeper and more V-shaped notch than 
in the modern wolves or foxes. The paroccipital processes are very small and_ project 
almost directly backward, as if to avoid the auditory bulla, with which they are not 
in contact at any point. 
The supraoceipital isa large bone, both high and broad; dorsally it is reflected 
over upon the cranial roof, and in this region is thickened and diploétic. 
The mastoid is exposed quite extensively upon the occipital surface, somewhat more 
so than in the modern representatives of the family, and as the distance between the 
paroccipital process and the postty panic process of the squamosal is greater than in the 
latter, the mastoid occupies a rather more lateral position. The mastoid process is very 
small, almost obsolete. 
The sphenoid bones cannot be described, as none of the specimens allow the limits 
of these elements to be gletermined. 
The tympanic differs in very important ways from that of Daphenus. In the first 
place it is inflated into a very much larger auditory bulla, filling out the entire fossa 
and leaving no part of the periotic exposed ; and in the second place, the posterior cham- 
ber of the bulla is ossified and fused with the anterior chamber. The line of junction 
between the two elements which compose the bulla is very plainly marked by a groove 
upon the external surface, and shows the posterior chamber to be considerably the smaller 
of the two. I have not been able to detect any, even partial, septum between the two 
chambers, but such a septum as that of Canis may well haye been present. The bulla 
is relatively as elongate as that of Canis, but is much narrower and more compressed, 
and therefore has a less inflated appearance. ‘The external auditory meatus isa very large, 
oval aperture, without any tubular prolongation, the borders being flat, except the ante- 
rior one, which forms a more prominent lip than in Canis and partially conceals the 
postglenoid foramen. The auditory bulla of Cynodictis is thus thoroughly cynoid in 
development and displays no resemblance to the characteristic viverrine type. 
The parietals are proportionately very large bones and make up the greater part of 
the sides and roof of the cranium. Throughout their length they unite to form a very 
low and weak sagittal crest, which becomes moderately prominent only at the concavity 
of the cranium formed between the occipital crest and the hinder wall of the cerebral 
fossa. Owing to the larger size and backward extension of the cerebral hemispheres, as 
well as to the lowness of the occipital crest, this concavity is shorter and much shallower 
