PREVIOUS TO THE LAST GEOLOGICAL REVOLUTION. 257 



exist ; of which two [Cynailurus and Speothos) may be con- 

 sidered sub-genera of Felis and Canis, while the other twOj 

 bear and hyaena, constitute proper genera. Thus the propor- 

 tion of genera between the former and the present period, is 

 as eight to fixe. Again, of the five existing genera, three, 

 namely, Felis, Cams, and Lutra, are common to both conti- 

 nents ; but Nasua and Eirara are peculiar to the new world. 

 The presence, therefore, of these two last genera among the 

 fossil Fauna, supplies one more link in support of the propo- 

 sition 1 have already laid down, that the animal world was 

 framed upon the same plan in the former epoch, as now. 

 Of the four fossil genera not now found in America, Cy- 

 nailurus and Speothos have each a living representa- 

 tive in the warm regions of the old world. Already in our 

 examination of Ruminantia, we are made acquainted with 

 a genus belonging to the extinct creation of this continent, 

 the antelope, which at least seemed to present a similar con- 

 nection ; but at the same time, as there remained some room 

 for doubt, I would not ground so important a result on an 

 indefinite fact. So also with reference to the examples I 

 have just produced, doubts may be entertained as to these 

 geographical relations ; partly, because the equivalent forms 

 are only to be considered as sub-genera ; and partly, because 

 it may be supposed, that from the great external resemblance 

 which the first ( Cynailurus), undoubtedly bore to the true genus 

 Felis, we may possibly hereafter discover its peculiar dental 

 system in some one or other of the less known existing spe- 

 cies of Felis on this continent. It is, therefore, better to 

 abstain from any positive decision on the subject at present ; 

 the rather, as the history of the next genus I am about to de- 

 scribe, shows the necessity of caution in grounding results 

 on negative evidence. The bear was believed, until within a 

 few years, in spite of Molina's account, to be peculiar to the 

 old world and North America : later discoveries, however, 

 have proved that at least one, if not several species, inhabit 

 the mountains of Peru and Chili. The latter are distinguished 

 from the others of their race by their inferior size : and as 

 we have seen that the fossil Brazilian bear exhibits the same 

 proportions, I consider this latter as nearer related to that of 

 the Andes, than to that, either of the old world or of North 

 America. Thus in this genus, we have a confirmation of 

 the supposition we hazarded respecting the antelope, which 

 affords another example of that very remarkable geographi- 

 cal relation, that the Andes now possess the representatives 

 of several animal forms, which, in ancient times extended 

 over the elevated plains of South America. The constant 



