THE PROBLEMS PRESENTED 29 



breathe an atmosphere of physiology rather than anatomy, or 

 function than form. 



Enough has been said here by way of defining the terms of 

 the issue. The negative we have to sustain is that the following 

 facts and observations declare that certain small modifications 

 cannot be governed by selection and are not correlated with useful 

 characters. It will be shown later that Professor Thomson's 

 stringent condition is not in all of them compiled with, but that, 

 in spite of this, the probability of their being valid examples of 

 Lamarckism in practice is immense. 



