i893. THE RECAPITULATION THEORY. 281 



the same species, did not investigation of their ontogeny reveal stages 

 resembHng the adults of pre-existing species belonging to the two 

 different genera. In these cases, it is the earliest stages that differ 

 most and afford the best proof not only as to their affinities with con- 

 temporary species, but as to their perished ancestry. It would be 

 rash for one who is no entomologist to hint that the resemblance of 

 the adult Culex, Corethva, and Chivonomtis is a similar case of con- 

 vergence ; but it is clear in the case of Dumortieria and Grammoceras 

 that "variation" apparently " affecting chiefly the structure of the 

 individual in early stages of development " has actually preserved to 

 us a record of the ontogeny. 



Another mistake of Mr. Hurst, is his refusal to admit more than 

 one method of variation. He appears to deny that variation occurs 

 at the close of ontogeny ; if an adult structure varies, he says in 

 effect, it ceases to exist as an adult structure at all. It does even- 

 tually do so, no doubt, but not immediately. The very same " change 

 in the constitution of successive generations of a species leading to 

 the production of a new species " does take place in the life-history 

 of a single generation. Ontogeny, in fact, forecasts phylogeny just 

 as much as it repeats it. An Ammonite that is smooth in the adult, 

 will become ribbed in old age ; this change takes place at earlier and 

 earlier periods in successive generations, till at last a form is attained 

 that has ribs in the' adult. Then we call it a new species. But this 

 new species is spinous in its old age ; gradually do the spines, in like 

 manner, appear sooner and sooner, till another species, that bears 

 spines in its maturity, is found in the rocks. A similar case is the ten- 

 dency of modern civilised man to adopt baldness as an adult 

 character, although one that has hitherto been regarded as purely 

 senile. Yet all these well-known instances of variation (and I use 

 the term precisely in Air. Hurst's own sense) " occur in a way utterly 

 unlike the way in which it does actually occur," /.^., within Mr. Hurst's 

 horizon. Of course, this is not the only method of variation ; there 

 are sports of differing degrees, and there is variation produced by 

 sexual mixture of different strains. If these alone were to be con- 

 sidered, we might, of course, be led to different conclusions, that is, 

 if we were persistently to shut our eyes to the plain facts of 

 palaeontology. 



The fact that absurdities and contradictions have arisen from too 

 zealous following of the Recapitulation Theory dees not actually 

 prove the conception false; nor, on the other hand, does the fact 

 that under its guidance we have made remarkable discoveries and 

 initiated fruitful investigations necessarily prove its truth ; at the 

 same time, it might possibly lead Air. Hurst to reconsider his con- 

 demnation if he were to make himself acquainted with the brilliant 

 researches of Hyatt and Buckman on Cephalopoda, R. T. Jackson on 

 Pelecypoda, and Beecher on Brachiopoda, not to mention many 

 writings in other tongues than our own, all which works have been 



inspired by the Recapitulation Theory. t- \ t:> 



^ J ^ J F. A. Bather. 



