1879.] NATURAL SCIENCES OP PHILADELPHIA. 173 



Lyncus, Raf. Pajeros, Lynx et Caracal, Gray. 



L. pajeros, Desm. South America. The Pampas. 



L. borealis, Gray. Northern Europe, Sweden. 



L. canadensis, Geoffr. North America. 



L. pardinus, Temm. Southern Europe, Turkey. 



L. isabellinus, Blyth. Thibet. 



L. rufus, Giildenst. North America. 



L. maculatus, Vig. and Horsf. North America, Mexico, and 



California. 

 L. caracal, Schreb. Southern Asia and Africa, Persia and 



Arabia. 



Neofelis, Gray. 



N. macrocelis, Temm. Himalaya (Hodgson), Malacca. 



N. brachyurus (Temm), Siam. Svvinhoe, Formosa (Swinhoe). 



TJncia, Gray, Cope emend. Leo, Tigris et Leopardus, Gray. 



U. coneolor, L. North and South America. 



U. auratus, Temm. Himalaya, Sumatra, Borneo. 



TJ. onca, L. South America, Mexico, Texas. 



U. chinensis, Gray. Pekin, mountain forests of the west. 



TJ. japonensis, Gray. Japan. 



TJ. pardus, L. Southern Asia, North, South, and West Africa. 



TJ. tigris, L. Asia. 



TJ. leo, L. Africa, India. 



TJ. irbis. Thibet. 



Cynaelurus, Wagler. Gueparda, Gray. 



C. jubatus, L. Africa, Asia, Persia, Cape of Good Hope. 

 ? C.ferox, Leidy (Aelurodon). Loup River, Nebraska. 



The successive order of the modifications of structure Which 

 define the above genera is not difficult to perceive, and it is inter- 

 esting to discover that, as in other cases, it coincides with the 

 succession in geologic time. The typical genera Uncia, Felis, etc., 

 are characterized by great specialization, and it is they which now 

 exist. The oldest found Dimctis, Nimravus, etc., are the least 

 specialized in most respects, and they disappeared before the close 

 of Miocene time. 



Since one of the special characters of the Felidse is the reduc- 

 tion in the number of the molar teeth by subtraction from both 

 ends of the series, an increased number of these constitutes re- 



