JANUAEY 1, 1915] 



SCIENCE 



9 



Surely not for the lack of accessible fields 

 of genetic research that are fertile and 

 varied enough to reward our best efforts, 

 as no one has more forcibly urged or more 

 brilliantly demonstrated by his own ex- 

 ample than Professor Bateson himself. 



Perhaps it would be the part of discre- 

 tion to go no further. But the remarkable 

 questions that Professor Bateson has raised 

 concerning the nature of evolution leave 

 almost untouched the equally momentous 

 problem as to what has guided its actual 

 course. In approaching my close I shall be 

 bold enough to venture a step in this direc- 

 tion, even one that will bring us upon the 

 hazardous ground of organic adaptations 

 and the theory of natural selection. I need 

 not say that this subject is beset by intri- 

 cate and baffling difficulties which have 

 made it a veritable bone of contention 

 among naturalists in recent years. In our 

 attempts to meet them we have gone to 

 some curious extremes. On the one hand, 

 some naturalists have in effect abandoned 

 the problem, cutting the Gordian knot with 

 the conclusion that the power of adapta- 

 tion is something given with organiza- 

 tion itself and as such offers a riddle that 

 is for the present insoluble. In another 

 direction we find attempts to take the prob- 

 lem in flank — to restate it, to ignore it — 

 sometimes, it would almost seem to argue 

 it out of existence. It has been urged in a 

 recent valuable work — by an author, I 

 hasten to say, who fully accepts both the 

 mechanistic philosophy and the principle 

 of selection — that fitness is a reciprocal re- 

 lation, involving the environment no less 

 than the organism. This is both a true and 

 a suggestive thought; but does it not leave 

 the naturalist floundering amid the same 

 old quicksands? The historical problem 

 with which he has to deal must be grappled 

 at closer quarters. He is everywhere con- 

 fronted with speciflc devices in the organ- 



ism that must have arisen long after the 

 conditions of environment to which they are 

 adjusted. Animals that live in water are 

 provided with gills. Were this all we could 

 probably muddle along with the notion that 

 gills are no more than lucky accidents. 

 But we encounter a sticking point in the 

 fact that gills are so often accompanied by 

 a variety of ingenious devices, such as res- 

 ervoirs, tubes, valves, pumps, strainers, 

 scrubbing brushes and the like, that are ob- 

 viously tributary to the main function of 

 breathing. Given water, asks the natural- 

 ist, how has all this come into existence 

 and been perfected? The question is an 

 inevitable product of our common sense. 

 The metaphysician, I think, is not he who 

 asks but he who would suppress it. 



For all that it would seem that some per- 

 sons flnd the very word adaptation of too 

 questionable a reputation for mention in 

 polite scientific society. Allow me to illus- 

 trate by a leaf taken from my own notebook. 

 I once ventured to publish a small experi- 

 mental work on the movements of the fresh- 

 water Hydra with respect to light. What 

 was my surprise to receive a reproof from 

 a friendly critic, because I had not been 

 content with an objective description of the 

 movements but had also been so indiscreet 

 as to emphasize their evident utility to the 

 animal. I was no doubt too young then — 

 I fear I am too old now — to comprehend 

 in what respect I had sinned against the 

 light. That was long ago. I will cite a 

 more recent example from a public dis- 

 cussion on adaptation that took place be- 

 fore the American Society of Naturalists a 

 year or two since. ' ' The dominance of the 

 concept of adaptation," said one natu- 

 ralist, "which now distinguishes our sci- 

 ence from the non-biological ones, is related 

 to the' comparatively youthful stage of 

 development so far attained by biology, 

 and not to any oiserved character in the 



