LAMARCK AND MR. DARWIN. 257 



theories," as they have been somewhat cheaply called, 

 are far from having had their last say. 



Returning to Mr. Darwin, we find, as we have already 

 seen, that it is hard to say exactly how much Mr. Darwin 

 differs from Lamarck, and how much he agrees with him. 

 Mr. Darwin has always maintained that use and disuse 

 are highly important, and this implies that the effect 

 produced on the parent should be remembered by the 

 offspring, in the same way as the memory of a wound 

 is transmitted by one set of cells to succeeding ones, 

 who long repeat the scar, though it may fade finally 

 away. Also, after dealing with the manner in which 

 one eye of a young flat-fish travels round the head till 

 both eyes are on the same side of the fish, he gives 

 (" Natural Selection," p. 188, ed. 1875) an instance of a 

 structure " which apparently owes its origin exclusively 

 to use or habit." He refers to the tail of some American 

 monkeys "which has been converted into a wonder- 

 fully perfect prehensile organ, and serves as a fifth 

 hand. A reviewer," he continues, .... "remarks 

 on this structure ' It is impossible to believe that in 

 any number of ages the first slight incipient tendency 

 to grasp, could preserve the lives of the individuals pos- 

 sessing it, or favour their chance of having and of rearing 

 offspring.' But there is no necessity for any such belief. 

 Habit, and this almost implies that some benefit, great 

 or small, is thus derived, would in all probability suffice 

 for the work." If, then, habit can do this and it is no 

 small thing to develop a wonderfully perfect prehensile 

 organ which can serve as a fifth hand how much more 

 may not habit do, even though unaided, as Mr. Darwin 



