45 



Plants respond to their surroundings. Individual plants 

 may be profoundly influenced, so may the race, yet there 

 appears to be no connection between this individual change 

 and the race change. In other words, the character of a 

 plant may, by peculiar conditions of feeding or exposure, 

 be much modified, but it has no power of transmitting this 

 modification to its offspring. The seed may be poor or well 

 filled out, according as the plant has been ill or well fed, 

 and a weak or robust plant may result, but no other con- 

 dition is transmitted. Thus many plants which, if grown 

 in ordinary soil have thin leaves, will, if the soil contains 

 much salt, become thick and fleshy, but will immediately 

 again produce thin-leaved young if their seed is planted 

 on normal soil. A fern growing on our mountain tops 

 is copiously hairy, but if it is brought down to a low eleva- 

 tion the new leaves gradually lose that condition. The 

 seed-producing parts of a plant are the oldest and best 

 fixed of its organs, and they appear to do their work along 

 fixed lines without transmitting any personally acquired 

 character. This is at variance with popular ideas, but is 

 the result of overwhelming evidence in both animal and 

 vegetable kingdom. The persistent change in habit is due 

 to other and racial causes, and will be dealt with in a 

 subsequent chapter. Therefore, we must look on the 

 adaptation of Myrtles to Australian conditions to be other 

 than the response of individuals. 



