Chap. x. SUMMARY. 345 



come widely divergent. Extinct forms are seldom 

 directly intermediate between existing forms ; but are 

 intermediate only by a long and circuitous course 

 through many extinct and very different forms. We 

 can clearly see why the organic remains of closely con- 

 secutive formations are more closely allied to each 

 other, than are those of remote formations; for the 

 forms are more closely linked together by generation : 

 we can clearly see why the remains of an intermediate 

 formation are intermediate in character. 



The inhabitants of each successive period in the 

 world's history have beaten their predecessors in the 

 race for life, and are, in so far, higher in the scale of 

 nature ; and this may account for that vague yet ill- 

 defined sentiment, felt by many palaeontologists, that 

 organisation on the whole has progressed. If it should 

 hereafter be proved that ancient animals resemble to 

 a certain extent the embryos of more recent animals 

 of the same class, the fact will be intelligible. The 

 succession of the same types of structure within the 

 same areas during the later geological periods ceases to 

 be mysterious, and is simply explained by inheritance. 



If then the geological record be as imperfect as I 

 believe it to be, and it may at least be asserted that 

 the record cannot be proved to be much more perfect, 

 the main objections to the theory of natural selection 

 are greatly diminished or disappear. On the other 

 hand, all the chief laws of palaeontology plainly pro- 

 claim, as it seems to me, that species have been pro- 

 duced by ordinary generation : old forms having been 

 supplanted by new and improved forms of life, produced 

 by the laws of variation still acting round us, and pre- 

 served by Natural Selection. 



q3 



