xn POST-PLEIOCENE FOSSILS. 



Those which have hitherto been regarded as of recent and European origin, are the 

 horse, sheep, hog and ox; and it must be reserved perhaps for future consideration to deter- 

 mine how far the negative proof of the non-existence of these animals in the country at the 

 time of its discovery may be regarded in each individual case sufficiently strong to settle 

 the question of his extinction and re-introduction, when so many of his associates and con- 

 temporaries have succeeded in maintaining an unbroken line of descent down to the 

 present day. 



