CHAPTER VILE 
CLASSIFICATION OF THE FORMS OF THE PRINCIPLES 
PRODUCING ALLOGAMIC EVOLUTION. 
I. TABLES OF FORMS, WITH BRIEF EXPLANATIONS 
The analysis presented in the two preceding chapters has revealed 
many factors, which are here brought together in tables so arranged 
as to show the more important of their relations to each other. (See 
pages 138-139.) 
1. Allogamic, Autogamic, and Agamic Evolution. 
A complete classification of the factors of organic evolution must 
include the principles producing differentiation of organisms multi- 
plying asexually, as wellas of those reproducing sexually. Moreover, 
the reproduction of self-fertilizing speciesis so unlike that of speciesin 
which cross-fertilization takes place (either in each generation or at 
the end of a series of generations), that it seems necessary to consider 
their methods of transformation separately. Following these dis- 
tinctions, organic evolution needs to be divided into three depart- 
ments, which may be called: 
Allogamic evolution, which relates to the evolution of cross-fertiliz- 
ing organisms; 
Autogamic evolution,* which relates to the evolution of self-fertil- 
izing organisms; and 
Agamic evolution, which relates to the evolution of organisms 
whose reproduction is continuously asexual. 
The investigation presented in this volume relates to allogamic 
evolution. 
* Karl Pearson, in 2nd ed. of ‘’The Grammar of Science,’ London, 1900, p. 423, 
uses the term “Autogamic Mating”’ to designate self-fertilization. 
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