62 CARNIVORA order hi 



the astragalus is deeply grooved superiorly and convex inferiorly, seldom 

 completely truncated. 



The Carnivora proper are divided into seven families : Canidae, Ursidae, 

 Procyo7iidae, Mustelidae, Viverridae, Hyaenidae, and Felidae, all of which are 

 represented in Tertiary and existing faunas. 



Family 1. Canidae. Dogs.i 

 '3.1.4.3-2. 



P'^ with moderate inner cusp, strongly developed primary cusps 



and long, shearing surface. P^ and P^, usually also P^, with secondary cusps. 

 Upper M tritubercular, broader than long and frequently with intermediate cusps. 

 M^ with high trigonid, moderately large metaconid and pitted, rarely trenchant 

 talonid. M^ flatter and smaller than My Paroccipital process prominent and 

 abutting on bulla. Extremities digitigrade, originally pentadactyl, later ivith pollex 

 and hallux greatly reduced. Claws not retractile. Tail long. Os penis present. 



The Canidae (comprising the dogs, wolves, jackals, and foxes) have at 

 present a cosmopolitan distribution. In external appearance as well as in 

 dentition, they resemble the Viverridae most closely, although early 

 differentiated from them as true Miacidae while in the Creodont stage. They 

 first appear in the Upper Eocene of Europe, the Amphicyoninae alone being 

 present in the Oligocene and Lower Miocene ; later, they become more 

 common in the Pliocene and Pleistocene. Their development is greatest 

 in the Middle Tertiary of North America, from which they have become 

 distributed to Europe through Asia, appearing also in South America. 



Subfamily 1. Cynodictinae. 



2-3 



—^ M. P slender, with secondary cusps ; upper M much wider than long, with 



intermediate cusps; lower carnassial with high and massive trigonid, basin-shaped 

 talonid. Humerus with entepicondylar foram,en. Extremities pentadactyl, semi- 

 digitigrade. Metapodia with hemispherical, distal articular ends. Astragalus 

 distally convex, claws partially retractile. 



The skeletal and dental characters most nearly resemble those of the 

 Viverridae, the distinguishing feature being the presence of three molars. 



Procynodictis Matthew and Wortman. Upper M lacking median tubercle. 

 Uinta beds (Upper Eocene). 



Protemnocyon Hatcher. C stout and compressed, P with lateral cusps. 

 Upper molars with protoconule. M'^ reduced ; lower molars with trenchant 

 talonid. Brain cavit}^ much inflated, sagittal crest very low ; atlas resembling 

 that of Canis. Supposed to be in the ancestral line of Mesocyon. White 

 River beds (Oligocene). 



^ Hatcher, J. B., Oligocene Canidae. Mem. Carnegie Mas., vol. i. , 1902. — Huxhy, Th., 

 Dental and cranial characters of tbe Canidae. Proc. Zool. Soc. London, 1880. — Merriam, J. C, 

 Pliocene and Quaternary Canidae. Univ. California Publ., 1903, 1913. — Peterson, 0. A., Description 

 of new Carnivores from the Miocene. Mem. Carnegie Mus. , vol. iv., 1910. — Scott, W. B., 

 Notes on the Canidae of the White River Oligocene. Trans. Amer. Philos. Soc, vol. xix., 1898. — 

 Stnder, Tlwodor, Die prahistorischen Hnnde. Abhandl. Schweiz. Paliiont. Ges., Bd. xxviii., 1901. 

 — Woldrich, J., Die Cauideu aus dera Diluvium. Denkschr. Wien. Akad., math.-naturw. Kl., 

 1878 ; Bd. Ixxxix. — Wortman, J. L., and Mattheiv, W. D. Bull. Amer. Mus. Nat. Hist., New 

 York, 1899. 



