236 



THE FLESH-EATERS. 



the Monodelphia, the resemblance of their 

 dentition to that of the marsupials still re- 

 mains, and this fact seems to point to mar- 

 supials as the forms from which those extinct 

 carnivores are to be derived. 



The equivocalness of the characters of 

 many of the primitive carnivores is an equally 

 remarkable fact. The oldest known carnivore, 

 the genus Arctocyon from the sandstone of 

 La Fere, in the French department of Aisne, 

 a formation belonging to the Lower Eocene, 

 was of the size of a wolf, and had intermediate 

 characters between the dogs and bears. 

 Several Miocene genera (Amphicyon, Hysen- 

 arctos) present similar affinities. Amphicyon 

 had a dentition so closely approaching that 

 of the dogs that one may fall into some 

 embarrassment in trying to distinguish these 

 remains. " But Amphicyon," says Gaudry, 

 " was a plantigrade and perhaps a climber 

 like the bears, while the true dogs are digiti- 

 grade, and are not climbers. The upper 

 canines of Amphicyon were much longer and 

 straighter than in the dogs; the premolars 

 and the carnassial were smaller, and,, on the 

 other hand, the surface occupied by the 

 tubercled, that is, by the omnivorous teeth, 

 was much larger in comparison with the 

 extent of the incisors; these characters con- 

 tribute to indicate relationships with the 

 bears." 



I will not enter further into these details. 

 Let it suffice to say that in Europe, as in 

 America, a number of these intermediate 

 genera have been found; that in the Eocene 

 there have been found connecting links be- 

 tween the Canida and Viverrida (Cynodon), 

 between the Viverrida and the Felida (Lim- 

 nofelis), and between the Mustelida and the 

 Felida (Pseudaelurus), and that in the Miocene 

 have been found connecting links between 

 the Viverrida and Hyaenida (Dititherium, 

 Hysnictis), and between the Viverrida and 

 the Mustelida (Lutrictis). 



It is thus established, that none of the 

 families now living is clearly represented in 



the Eocene strata; but that there we may 

 find the stocks of the Canida, Ursida, Viver- 

 rida, Mustelida, and Felida more or less 

 marked by subordinate relationships. On 

 the other hand, almost all the important 

 carnivorous families are clearly represented 

 in the Miocene either by genera still living 

 or by extinct genera. The only exception is 

 the family of the bears, including both Large 

 and Small Bears, remains of which have not 

 yet been discovered lower down than the 

 Pliocene. This fact may be regarded as all 

 the more striking since the most prominent 

 characters of the bear family, apart from the 

 dentition, namely, the clumsy limbs and 

 plantigrade feet, appear to have been common 

 to all Eocene forms. But when we remember 

 that the plantigrade Arctocyonida( Amphicyon, 

 Hyamarctos, &c.) are still very abundant in 

 the Miocene strata, that at this time they 

 had a very wide geographical distribution 

 both in the Old and the New World, we 

 cannot resist the idea that the bears are the 

 direct descendants of these families, of which 

 they have retained the clumsy forms and the 

 plantigrade mode of progression, while their 

 dentition became gradually more and more 

 adapted to an omnivorous diet. 



The present families have inhabited the 

 same great geographical regions from the 

 time when they became fixed. The gigantic 

 Machairodi roamed over both hemispheres 

 in the same way as the present Felida now 

 do, and were found there along with Canida 

 and Mustelida. The Viverrida and Hysenida 

 were then excluded from the New World, as 

 the Procyonida were from the Old. All these 

 varied modifications or differentiations, to 

 use the technical term, have thus been 

 effected independently in the two hemispheres, 

 and have originated in separate mixed forms 

 and intermediate stocks indigenous in each. 

 These facts are another proof that the two 

 great continental masses have been separate 

 since the Eocene period. Not till Quaternary 

 times, when the ice -masses had restored 



