No. 602] TRE SELECTION PROBLEM 



71 



natural enemies. This result, it may be said, has been 

 confirmed in subsequent years. Eeighard,^** in one of the 

 most beautiful experimental studies of natural selection 

 which has ever been made, found that there was no rela- 

 tion between the colors of coral, reef fishes and their 

 elimination by natural enemies. 



While the researches which have been mentioned do 

 not exhaust the literature, they are all for which time can 

 be spared now, and they are fairly representative of the 

 whole of the distinctly meager experimental and quanti- 

 tative evidence regarding selective elimination. On the 

 whole, the net result is not so clear-cut and outstanding 

 as could be wished. If a scientific person came here from 

 some other planet with an earnest desire to inform him- 

 self about selective elimination, of which he had not 

 before known anything, and read all the available real 

 evidence on the point, he would be sure to come to some 

 such conclusion as this : that in some cases natural elim- 

 ination is certainly in some degree selective, while in other 

 cases it certainly is not; and in the most favorable cases 

 of all the selection is apparently not very rigorous. 

 Grossly teratological abnormalities are eliminated. But 

 the smaller deviations from type, which in theory ought 

 to furnish the basis of selection, appear upon quantitative 

 study less generally and sliar]ily determinative of sur- 

 vival than might reasonably have been expected theo- 

 retically. The case regarding this first element of the 

 theory of natural selection certainly seems far loss strong, 

 under the critical eye of experiment and measurement, 

 than those of us who were nourished on TVeismnnn. 

 Romanes, and their like, would have supposed ]^()ssi])1p 

 twenty years ago. Still the writer lias no desire to bo 

 controversial about the matter and if nnv ono is dis]io-oil 

 to draw the opposite conclusion from tlio facts ho is en- 

 tirely welcome to. 



Let us now turn to the consideration of our second rule, 

 which must be fullv enforced if nntnral selection is to he 

 an important factor in the causation of evolutionary 



"Reighard, .T.. Carnegie Trf^itution. Publication 103, pp. 257-32.5, 1908. 



