No. 602] THE SELECTION PROBLEM 



The tale here is not a long one. Indeed it is surpris- 

 ingly brief, considering the mass of literature which the 

 theory of natural selection in its more formally logical 

 aspects has engendered. We have first the pioneer work 

 of Weldon^ with Carcinus, in which a selective elimina- 

 tion of individuals different physically from the survivors 

 was first demonstrated numerically, the eliminating en- 

 vironmental factor being the silt in the water. This was 

 followed by a number of investigations of a more or less 

 similar character, notably those of Poulton and Sanders^ 

 with Vanessa, and of di Cesnola^ with Mantis, in which 

 different colored forms of these insects were exposed to 

 elimination by natural enemies, chiefly birds, with the 

 result that there was found to be some relation between 

 the chances of elimination and the degree to which the 

 insect matched its background. Bumpus^ studied sur- 

 viving and eliminated English sparrows after a severe 

 winter storm. Crampton^ measured the surviving and 

 eliminated pupsB of Philosamia, the elimination having 

 been produced by wholly natural causes. Davenport,^® 

 in a very small lot of chickens, found that those killed by 

 crows were colored differently from those eliminated. 

 Lutz^i found in Drosophila some differences in type be- 

 tween survivors and eliminated. Harris^ ^ }ias shown that 

 among seedling beans abnormal types perished more fre- 

 quently than strictly normal types under the same field 

 conditions. The same author^ ^ has also made extended 



5 Weldon, W. F. E., Proc. Boy. Soc, Vol. XLVII, pp. 360-379, 1894. Also 

 see Brit. Assoc. Eept., Bristol (1898), pp. 887-902, 1899. 



8 Poulton and Sanders, Kept. Brit. Assoc. (Bristol), pp. 906-909, 1899. 



7 di Cesnola, A. P., Biometrilca, Vol. Ill, pp. 58-59, 1909. 



sBumpus, H. C, Biological Lectures, Woods Hole, 1908, pp. 209-226, 

 Boston, 1899. 



»Crampton, H. E., BiometnTca, Vol. Ill, pp. 113-130, 1904. 



10 Davenport, C. B., Nature, Vol. LXXVIII, p. 101, 1908. 



" Lutz, F. E., Bulletin Amer. Mus. Nat. Bist., Vol. XXIV, pp. 605-624, 



12 Harris, J. A., Science, N. S., Vol. XXXVI, pp. 713-715, 1912. 

 "Harris, J. A., Science, N. S., Vol. XXXII, pp. 519-528, 1910. Pop. 



in Biometrika, Amer. Nat. and^elsewhere. 



