CHAP. XII.] 



DIFFERENT KINDS OF CATS. 



437 



§ 19. Yet another miocene genus has heen described * by Professor 

 Cope. It is named Pogoxodon, and its skull is about one-sixth 

 smaller than that of the tiger. " The canine is large and compressed, 

 as in MachcBrodus, and has serrulate anterior and posterior cutting 

 edges." The symphysis is much widened to protect the canines. It 

 differs from the Macha^nodonts in having an additional inferior pre- 

 molar tooth. The skull of this animal is singularly elongated, and 

 there are three premolars in the lower jaw, while the width of the 



Fig. 180. — Skull of rnQownhm i^lntycoins (Cope), from Orecox. 



diastema between the upper canine and the first premolar (which 

 is in place) is such as to seem as if another small premolar may 

 have existed. 



A very curious and exceptional eocene form of cat has been 

 named Eusmilus.'\ It differs from all other known felines in having 

 only four incisors in the lower jaw, and a pair of small canines sepa- 

 rated by a very long diastema from the next teeth, which consist 

 only of one premolar and one sectorial true molar. The lower jaw 

 is enormously widened towards its symphysis to protect the large 

 upper canines. It represents the characters of a llcsh-eating, pre- 

 dacious animal of the cat-kind, carried out to an extreme degree. 

 Professor Cope considers Eusmilus as forming the culminating deve- 

 lopment of the Machffirodont type of structure (Fig. 190). 



§ 20. A genus named JEho-odon, has been founded by Professor 

 Leidy % on an upper sectorial tooth found by Dr. Hayden at the 

 Loup River, Nebraska. It closely resembles the corresponding 

 tooth of the cheetah in the abortion of the internal cusp. 



A genus termed Limnofeiis has been instituted § to designate 



* See the American Naturalist for ] 

 Februaiy, 1880, p. 143, and for Decern- i 

 ber, 1879, p. 798&. i 



+ By M. Gervais in the 2nd part of 

 his Zoologie et Paleontologie Gencrales, 

 1876, pp. 53 and 54, plate 12. See also 

 Filhol, Eecherches sur les Phosphorites 

 de Quercy, Ann. des Sc. Geologiquf^s, 

 vol. viii., 1877, p. 321, audvol. vii., 1876, 



p. 153, plate 28. 



J Journal of the Acad, of Nat. Sc. of 

 Philadelphia ; Mammals of Nebraska, 

 p. 68, plate 1, figs. 13 and 14. 



§ American Journal of Science and 

 Arts, vol. iv., August, 1872. See also 

 Silliman's Journal, 3rd series, vol. iv., 

 1872, p. 202. 



