LAMARCK'S LAWS INCONSISTENT 145 



thousands of generations moulded the individuals of 

 a given species of organism, and determined as each 

 individual developed and grew " responsive " quantities 

 in its parts (characters) ; yet, as Lamarck tells us, and 

 as we know, there is in every individual born a potentiality 

 which has not been extinguished. Change the normal 

 conditions of the species in the case of a young individual 

 taken to-day from the site where for thousands of genera- 

 tions its ancestors have responded in a perfectly defined 

 way to the normal and defined conditions of environment; 

 reduce the daily or the seasonal amount of solar radiation 

 to which the individual is exposed ; or remove the aqueous 

 vapour from the atmosphere ; or alter the chemical com- 

 position of the pabulum accessible; or force the individual 

 to previously unaccustomed muscular effort or to new 

 pressures and strains ; and (as Lamarck bids us observe), 

 ,in spite of all the long-continued response to the earlier 

 normal specific conditions, the innate congenital poten- 

 tiality shows itself. The individual under the new 

 quantities of environing agencies shows new responsive 

 quantities in those parts of its structure concerned, new 

 or acquired characters. 



' So far, so good. What Lamarck next asks us to 

 accept, as his " second law ", seems not only to lack the 

 support of experimental proof, but to be inconsistent with 

 what has just preceded it. The new character, which is 

 ex hypothesi, as was the old character (length, breadth, 

 weight of a part) which it has replaced — a response to 

 environment, a particular moulding or manipulation by 

 incident forces of" the potential congenital quality of the 

 race — is, according to Lamarck, all of a sudden raised 

 to extraordinary powers. The new or freshly acquired 

 character is declared by Lamarck and his adherents to 

 be capable of transmission by generation ; that is to say, 

 it alters the potential character of the species. It is no 

 longer a merely responsive or reactive character, deter- 

 mined quantitatively by quantitative conditions of the 

 environment, but becomes fixed and incorporated in the 

 potential of the race, so as to persist when other quanti- 

 tative external conditions are substituted for those which 



