222 The Palaeontological Record. //. Plants 



surprising ; their presence may well serve as an incentive to further 

 research but does not, as it seems to the writer, justify the assump- 

 tion of changes in the past, wholly without analogy among living 

 organisms. 



As regards the succession of species, there are no greater au- 

 thorities than Grand'Eury and Zeiller, and great weight must be 

 attached to their opinion that the evidence from continuous deposits 

 favours a somewhat sudden change from one specific form to another. 

 At the same time it will be well to bear in mind that the subject of the 

 "absence of numerous intermediate varieties in any single formation" 

 was fully discussed by Darwin 1 ; the explanation which he gave may 

 go a long way to account for the facts which recent writers have 

 regarded as favouring the theory of saltatory mutation. 



The rapid sketch given in the present essay can do no more than 

 call attention to a few salient points, in which the palaeontological 

 records of plants has an evident bearing on the Darwinian theory. 

 At the present day the whole subject of palaeobotany is a study in 

 evolution, and derives its chief inspiration from the ideas of Darwin 

 and Wallace. In return it contributes something to the verification of 

 their teaching ; the recent progress of the subject, in spite of the 

 immense difficulties which still remain, has added fresh force to 

 Darwin's statement that "the great leading facts in palaeontology 

 agree admirably with the theory of descent with modification through 

 variation and natural selection 2 ." 



1 Origin of Species, pp. 275282, and p. 312. " Ibid. p. 313. 



