416 HISTORICAL GEOLOGY. 



It is needless to repeat that these last three heads he- 

 long to the present epoch. 



Conclusions. 



1. We have thus traced man back to the Mid-Quater- 

 nary. It is possible that he may hereafter be traced still 

 further back ; but this seems very improbable. No mam- 

 malian species now living can be traced further back than 

 the Quaternary. Man belongs to the present mamma- 

 lian fauna, and probably came in with other mammalian 

 species in the Quaternary. 



2. We have not yet been able to find any undoubted 

 transition forms or connecting links between man and the 

 highest animals.* The earliest known man, the river- 

 drift man, though in a low state of civilization, was as 

 thoroughly human as any of us. 



3. The amount of time which has elapsed since man 

 first appeared is still doubtful. Some estimate it at more 

 than a hundred thousand years some only ten thousand. 

 The question should not be regarded as of any impor- 

 tance, except as a question of science. 



* Such a link is supposed, by many, to have been recently found 

 in Java, and named Pithecanthropus. We wait for more evidence. 



