70 LECTURES ON EVOLUTION m 



the remains of these animals in the older rocks 

 in those which were deposited before the Carbon- 

 iferous epoch. Fishes we do find, in considerable 

 number and variety; but the great whales are 

 absent, and the fishes are not such as now live. 

 Not one solitary species of fish now in existence is 

 to be found in the Devonian or Silurian formations. 

 Hence we are introduced afresh to the dilemma 

 which I have already placed before you : either 

 the animals which came into existence on the fifth 

 day were not such as those which are found at 

 present, are not the direct and immediate ancestors 

 of those which now exist ; in which case, either 

 fresh creations of which nothing is said, or a 

 process of evolution, must have occurred ; or else 

 the whole story must be given up, as not only 

 devoid of any circumstantial evidence, but contrary 

 to such evidence as exists. 



I placed before you in a few words, some little 

 time ago, a statement of the sum and substance of 

 Milton's hypothesis. Let me now try to state as 

 briefly, the effect of the circumstantial evidence 

 bearing upon the past history of the earth which 

 is furnished, without the possibility of mistake, 

 with no chance of error as to its chief features, by 

 the stratified rocks. What we find is, that the 

 great series of formations represents a period of 

 time of which our human chronologies hardly 

 afford us a unit of measure. I will not pretend 

 to say how we ought to estimate this time, in 



