362 THE CANADIAN NATURALIST. [Vol. X. 



lets (the livinLi' species) passing upwards from the Pleiocene, a tree 

 of life, with liviog Mammalia for its fruit and foilage. Were 

 the extinct species taken into account, it would be seen that 

 they fill up the intervals separating one living form from another, 

 and that they too grow more and more like the living forms as 

 they approach nearer to the present day. It mu:;t be remem- 

 bered that in the above definitions the fossil marsupials are pur- 

 posely ignored, because they began their specialisation in the 

 Secondary period, and had arrived in the Eocene at the stage 

 which is marked by the presence of a living genus — the opossum 

 (Didelj)hi/s) . 



It will be seen from the examination of the above table, that 

 our inquiry into the antiquity of man is limited to the last four 

 of the divisions. The most specialised of nil animals cannot be 

 looked for until the higher Mammalia by which he is now sur- 

 rounded were alive. We cannot imagine him in the Eocene asre, 

 lit a time when animal life was not sufficiently differentiated to 

 present us with any living genera of placental mammals. Nor is 

 there any probability of his having appeared on the earth in the 

 Meiocene, because of the absence of the higher placental mam- 

 mals belonging to living species. It is most unlikely that man 

 should have belonged to a fauna in which no other living species 

 •of mammal was present. He belongs to a more advanced stage 

 ■of evolution than the mid-Meiocene of Thenay, as may be seen by 

 a reference to the preceding table. Up to this time the evolu- 

 tion of the amimal kingdom had advanced no further than the 

 Simadae in the direction of man, and the apes then haunting the 

 forests of Italy, France, and Germany, represent the highest type 

 •of those on earth. 



We may also look at the question in another point of view. 

 If man were upon the earth in the Meiocene age, it is incredible 

 that he should not have become something else in the long lapse 

 of a2;es. and durinu' the chano-es in the conditions of life by which 

 all the Meiocene land Mammalia have been so profoundly afi"ected, 

 that they have been either exterminated, or have assumed new 

 forms. It is impossible to believe that man should have been 

 an exception to the law of change, to which all the higher Mam- 

 malia have been subjected since the Meiocene age. 



Nor in the succeeding Pleiocene age can we expect to find man 

 upon the earth, because of the very few living species of placental 

 mammals then alive. The evidence brought forward by Professor 



