THE DESCENT OF THE PRIMATES 3 



most venerable tree of descent, that most real 

 and palpable pedigree, by which all things living 

 at this present moment are directly connected 

 with their ancestral forms, that existed in pre- 

 ceding geological epochs, as far as the earth's 

 past history reveals the presence upon it of living 

 beings. 



Henceforth there can thus be no two competing 

 or rival systems, between which biologists may 

 choose according to their convenience. There 

 is only one, and every conscientious naturalist 

 should strive to disentangle, with all the tenacity 

 and accuracy he is capable of, the complexity of 

 as many of its twigs or branches as may happen 

 to be within his reach. 



If there is one fact which in the last twenty- 

 five years has become self-evident, it is the com- 

 paratively insignificant place which the whole 

 number of living species, as we know them, 

 occupies in this immense tree of descent. Life 

 reaches down into the early stages of the earth's 

 youth, and there already we find it divided into 

 minor stems and branches, the majority of which 

 do not send up off-shoots into the present period. 

 Fortunately, palaeontology here steps in, and for 

 the animals or plants of bygone geological 

 epochs of which we shall forever miss the possi- 



