64 Darwin, and after Darwin. 



species we recognized as reflex actions on the one 

 hand, and instinctive actions on the other. Hence, 

 if there be any such thing as "use-inheritance' at 

 all, it is in the domain of reflex actions and instinc- 

 tive actions that we may expect to find our best 

 evidence of the fact. Therefore I will restrict the 

 present line of evidence — (A) — to these two classes 

 of phenomena, as together yielding the best evidence 

 obtainable within this line of argument. 



The evidence in favour of the Lamarckian factors 

 which may be derived from the phenomena of reflex 

 action has never, I believe, been pointed out before ; 

 but it appears to me of a more cogent nature than 

 perhaps any other. In order to do it justice, I will 

 begin by re-stating an argument in favour of these 

 factors which has already been adduced by previous 

 writers, and discussed by myself in published corre- 

 spondence with several leaders of the ultra-Darwinian 

 school. 



Long ago Professor Broca and Mr. Herbert Spencer 

 pointed to the facts of co-adaptation, or co-ordination 

 within the limits of the same organism, as presenting 

 good evidence of Lamarckian principles, working in 

 association with natural selection. Thus, taking one 

 of Lamarck's own illustrations, Mr. Spencer argued 

 that there must be numberless changes — extending to 

 all the organs, and even to all the tissues, of the 

 animal — which in the course of many generations 

 have conspired to convert an antelope into a giraffe. 

 Now the point is, that throughout the entire history 

 of these changes their utility must always have been 

 dependent on their association. It would be useless 



