326 NOTES ON THE CANID® OF THE WHITE RIVER OLIGOCENE. 
the genus Daphenus Leidy, which has long been known, though but very imperfectly, and 
several partially preserved skeletons permit an almost complete account of its osteology to 
be given. 
DAPHAENUS Leidy. 
Proc. Acad. Nat. Sci. Phil., 1853, p. 393. Amphicyon Leidy (non Pomel), ibid. 
1854, p. 157; Het. Mamm. Fauna Dak. and Nebr., 1869, pp. 32, 359; Cope, Ter- 
tary Vertebrata, pp. 894, 896. Canis Cope, Ann. Rep. U. S. Geolog. Surv. Terrs., 
1873, p. 505. 
This genus represents nearly the most primitive type of dogs which has so far been 
determined from the Tertiary deposits of North America. It was originally described 
and named by Leidy, who afterward mistakenly referred it to the European genus 
Amplhicyon, a reference which was also adopted by Cope. Though more than forty 
years have thus elapsed since the first discovery of these animals, singularly little has 
been known about them, for the material obtained has been very scanty and very badly 
preserved. Fragments of jaws, a few very imperfect skulls and fewer limb-bones have 
hitherto been the only specimens found, in spite of long and careful search, and beyond 
the fact that Daphenus was apparently a primitive member of the canine phylum, little 
could be predicated of it. 
The new material gathered by Messrs. Gidley and Wells fortunately removes this 
difficulty and gives us information regarding nearly all parts of the skeleton of these 
curious animals. These skeletal characters are of a very surprising nature and their 
interpretation is by no means easy. Especially remarkable are the many points of 
resemblance which we find between the structure of Dapheenus and the corresponding 
parts of such primitive Machairodonts as Dinictis. Aside from the dentition and the 
shape of the mandible, these resemblances in structure between the primitive dogs and 
the early sabre-tooth cats are ubiquitous, and recur in the structure of the skull, of the 
vertebree, of the limbs and of the feet. To bring out the full force of these remarkable 
characteristics, it will be necessary to enter into a detailed and somewhat tediously minute 
description of the osteology of Daphanus, so that the means of comparison may be com- 
pletely laid before the reader. 
lL. Tee Dentirron. 
The dental formula of the genus is I 3, C4, P 4, M 3, the same as that of Amphi- 
cyon, a resemblance which caused the erroneous identification of the two genera already 
referred to. 
A. Upper Jaw (Pl. XIX, Fig. 2).—The incisors are closely crowded together and 
form a nearly straight transverse row; they are smaller and occupy less space both 
