I 88 APPENDIX II — INTENSIVE SEGREGATION. 



(4) Emotional transformation. — Dr. C. V. Riley, late of the National 

 Museum, Washington, has called attention to the influence of parental 

 emotions (especially maternal emotions during the term of pregnancy) 

 as a factor in evolution (Address "On the Causes of Variation," before 

 the Section of Biology, American Association, August, 1 888 ; also in 

 Popular Science Monthly, vol. xxxlv, pp. 81 1-8 16). 



(5) The cumulative development of adaptations through "the 

 survival of the fittest" when the fittest are other than average forms. 

 This is the principle of unbalanced selection producing selectional 

 transformation. 



(6) Transformation produced by the indiscriminate destruction of 

 a portion of a species, with the accompanying probability that the 

 remaining portion will not possess all the characters possessed by the 

 species previous to the elimination. This principle I call "unbalanced 

 indiscriminate el i mi nation," producing indiscriminate elimination al 

 transformation. 



(7) Transformation produced by different degrees of amalgama- 

 tion of the varieties and races which have resulted from previous segre- 

 gations. In most species there is a constant process of amalgamation 

 by which thousands of minor varieties are absorbed; but when the 

 process extends beyond ordinary limits, and the barriers that have 

 divided well-marked races give way, transformation must follow. 

 This principle I call diversity of amalgamation producing amalgama- 

 tional transformation. 



(8) The cumulative development of the more fertile of the forms 

 that are equally adapted. In other words, transformation produced 

 by diversity in the relative fertility of varieties that are equally 

 adapted to the environment and the constitution of the species, or by 

 change in the degrees of fertility possessed by the same variety at dif- 

 ferent times and in different places. This principle I call unbalanced 

 fecundity, or unbalanced fecundal selection, producing fecundal trans- 

 formation. 



Of these principles all except the sixth, seventh, and eighth have 

 been more or less discussed by writers on biology, though some of the 

 forms of selection depending on the relations in which the members 

 of a species stand to each other have never been pointed out, and 

 many writers have failed to observe that selection often produces fixity 

 of type instead of transformation, and that divergence can not be pro- 

 duced through diversity in the kinds of selection without the coopera- 

 tion of isolation, and may be produced without exposure to different 

 environments. 



