THE METHOD OF EVOLUTION 13 



them. They have theories as to how variations 

 arise.' But we need not pause to consider them. 

 They are not relevant to our inquiry. The 

 essential fact is that Neo-Darwinians strenuously 

 deny that variations arise in the manner laid down 

 by Lamarck ; in other words, they strenuously deny 

 the transmission of acquired traits. The reader 

 will note that Darwin merely accepted the 

 indubitable fact that offspring differ from their 

 parents in that they are superior or inferior, and 

 founded his theory on the supposition that, as a 

 general rule, the superior individuals are selected 

 by Nature to continue the race. He did not 

 attempt by his theory to explain how the differences 

 arose. ^ Lamarck did more. He attempted to go 

 deeper than Darwin. He assigned a particular 

 cause for the differences. He supposed that 

 parents transmitted their acquirements to offspring, 

 and, on that supposition, founded his theory of 

 evolution. 



Let us now return to our illustrations. The 

 followers of Lamarck attribute the long neck of 

 the modern giraffe to the transmitted effects of 

 stretching. They think that ancestral giraffes 

 lengthened their necks by stretching upwards, and 



^ Vide Appendix B. 



2 At any rate, the attempt is not implied in his theory of Natural 

 Selection. He did attempt it in his theory of Pangenesis, and failed 

 more dismally than Lamarck. 



