NOTES ON THE CANIDiE OF THE WHITE RIVER OLIGOCENE. o4l 



of the luinbar vertebrae to those of the contemporary Machairoclont Dlnictis is very 

 great. Another similarity in the structure of the lumbar vertebrae between Daphcenus 

 and the felines consists in the great height and heaviness of the metapophyses, which are 

 much better developed than in the recent Canidce; on the last lumbar these processi - 

 become very much reduced and are, in fact, almost rudimentary. The anapophyses are 

 smaller than on the thoracic vertebra? and diminish in size on each successive vertebra 

 posteriorly ; only on the first and second are they very large and prominent. In the 

 existing representatives of the Canidce these processes are rudimentary, except on the 

 first lumbar, where they are small. This constitutes another point of resemblance 

 between Daphcenus and the cats, and emphasizes the statement already made, that the 

 posterior thoracic and lumbar vertebras of this Oligocene dog, for as such it must be 

 regarded, are decidedly more feline than canine in appearance, using those terms only 

 with reference to their modern application. 



The sacrum (PL XX, Fig. 14) consists of three vertebrae, and, in correspondence 

 with the great development of the tail, it resembles that of the larger cats in many 

 respects. Only the first sacral vertebra has any contact with the ilium and bears massive 

 pleurapophyses. Tbe centra are much larger and heavier than in the modern dogs and 

 the postzygapophyses much more prominent. The resemblance between the sacrum of 

 Daphcenus and that of the large cats is not very close, and the following differences may 

 be noted : (1) the neural spines are much lower and weaker ; (2) the neural canal is 

 smaller ; (3) the transverse processes of the second, and especially of the third vertebra, 

 are decidedly shorter, so that the posterior portion of the sacrum appears much narrower. 

 From the sacrum of the recent clogs that of Daphcenus differs particularly in its greater 

 proportionate length and massiveness. 



Caudal Vertebrce (PL XIX, Figs. 9, 10). — In none of the specimens of the collection 

 is the tail completely preserved, the largest number of vertebrae found being thirteen of 

 one individual and eleven of another, but enough remains to satisfactorily demonstrate 

 its character. The tail is remarkably long and stout and is, in fact, almost as well 

 developed as in the leopard or tiger, and, consequently, is much longer and thicker than 

 in any of the existing Canidw. 



The first caudal vertebra is quite like that of the lion, but is relatively lighter and 

 more slender in all its parts, and has a short but distinct neural spine ; the zyga- 

 pophyses are very prominent, and even the metapophyses are distinctly shown ; the 

 transverse processes are very long, but are not so broad proportionately as in the lion, 

 and are quite strongly recurved. Posteriorly the caudal vertebrae become successively 

 more and more slender and elongate, while all of the processes are gradually reduced in 

 size. The middle region of the tail is made up of extraordinarily elongate vertebrae, 



