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NOTES ON THE CANIDH OF THE WHITE RIVER OLIGOCENE. 
II, THe Sxunn (Pl. XIX, Figs. 1-7). 
The skull of Daphenus is exceedingly primitive in character and plainly shows 
many traces of the creodont ancestry of the genus. Unfortunately, well-preserved skulls 
are exceedingly rare and none of the species is represented by an altogether complete 
specimen. However, seyeral more or less imperfect specimens haye been recovered, 
which together give us information concerning nearly all parts of the skull. 
As in the creodonts generally, the cranial region, reckoning from the anterior edge 
of the orbits backward, is exceedingly elongate, while the face in front of the orbits is 
very short, slender and tapering. The elongation of the cranium is not due to an enlarge- 
ment of the cerebral fossa, which on the contrary is short, narrow and of relatively small 
capacity. The postorbital constriction, which marks the anterior boundary of the cerebral 
fossa, is notably deep and is remoyed much farther behind the orbits than in Canis. On 
the other hand, the cerebellar fossa is long, and the postglenoid processes occupy a more 
anterior position than in the existing species. In consequence of the elongate cranial 
region, the zygomatic arches are very long, as in the more primitive types of creodonts. 
The upper contour of the skull is nearly straight, the descent at the forehead being yery 
slight and gradual, which gives to the skull an alopecoid rather than a thooid aspect. 
This resemblance is, however, entirely superficial, for the frontal sinuses are large and 
well developed, as in the thooid series of the modern Canide. The sagittal crest is low, 
but varies in the different species, being decidedly thicker and more prominent in the 
larger and heayier D. vetus than in the smaller and lighter D. hartshornianus. 
Turning now to the more detailed study of the elements which make up the skull, 
we shall find a number of striking and significant differences from the existing repre- 
sentatives of the family, though the general aspect of the whole is distinctively canine. 
The dasioccipital is broad and quite elongate and has a much more decided median 
keel than Canis. All the occipital bones are firmly ankylosed in the specimens at my 
disposal ; hence, in the absence of sutures, it will be necessary to deseribe the compound 
bone as a whole, without much reference to the elements of which it is made up. The 
occiput is of quite a different shape from that found in the existing members of the 
family, being broader, lower, and with a wide, gently arched dorsal border or crest (see 
Pl. XTX, Fig. 3); in Canis this crest is pointed and somewhat like a Gothic arch in 
shape. The occipital crest is thin, but much more prominent than in Canis, which is 
due to the larger and deeper depressions of the cranial walls behind the occipital lobes 
of the cerebral hemispheres, the shape of which is plainly visible externally. The 
foramen magnum has much the same low and broad outline as in Canis. The 
condyles are low, but well extended transversely, and on the ventral side they are. sepa- 
