£04 GEOEGE JOHN EOMANES 18S1- 



always seemed to me ih.it it is comprised under 

 Darwin's general category of causes internal to the 

 organism (or, in his terminology, causes due to ' the 

 nature of the organism '). But besides this, he recog- 

 nised the category of causes external to the organism 

 (or the so-called Lamarckian principles of direct 

 action of environment, plus inherited efforts of use 

 and disuse). Now, anyone who accepts this latter 

 category as comprising verce causes, obviously has a 

 larger area of causality on which to draw for his 

 theoretical explanations of variability, than has a 

 man who expressly limits the possibility of such 

 causes to the former category. This is all that I 

 had in my mind when writing the line in the ' Con- 

 temporary Eeview ' which led you to suppose that I 

 was expounding W. without having read him ; and 

 although I freely allow that the meaning was one 

 that required explanation to bring out, you may 

 remember that this meaning had nothing whatever 

 to do with the subject which I was expounding, 

 and therefore it was that I neglected to draw it out. 

 You will observe that, so far as the present matter 

 is concerned, it does not signify what views we 

 severally take touching the validity of Lamarckian 

 hypotheses. The point is, that anyone who sees 

 his way to entertaining thern thereby furnishes 

 himself with a larger field of causality for explaining 

 variations than does a man who limits that field 

 to causes internal to organisms — even though, like 

 W., he suggests an extension of the latter. 



And now about the ' Athenaeum.' I fear you think 

 I have been taking an unfair opportunity of giving 



