278 DIVERGENT EVOLUTION THROUGH SEGREGATION. 
which 1 emphasize, that all divergence of a permanent character, 
whether beneficial or non-beneficial, is dependent on se-generation, 
either separative or segregative. 
PRELIMINARY DEFINITIONS. 
Believing that great obscurity has often been introduced into the dis- 
cussion of biological subjects by the use of terms of uncertain import, 
I have endeavored to obtain greater precision by giving definitions of 
the terms I have introduced; and for the sake of indicating what words 
are thus used with special and definite meanings, they have been dis- 
tinguished by capitals. A few of these definitions are here given, and 
others will be given in the body of the paper. 
An Inter-generant, or Inter-generating Group, is a group of individuals 
so situated and so endowed that they freely cross with each other. 
Se-generation, or Independent Generation. In harmony with the funda- 
mental doctrines of evolution, [assume that each species was at one time 
a Single inter-generant; but we find that many species are now divided 
into two or more inter-generants, between which there is little or no 
inter-crossing. This state of freedom from crossing I call Se-generation. 
Se-generation is of two kinds, Separate Generation and Segregate Gen- 
eration. 
Separate generation, or separation, is the indiscriminate division of 
a species into groups that are prevented from freely crossing with each 
other. 
Segregate gereration, or segregation, is the inter-generation of similar 
forms and the prevention of inter-generation between dissimilar forms. 
Select generation, or selection, is the partial or complete exclusion of 
certain forms from the opportunity to propagate, while others succeed 
in propagating. The generation of any form is select with reference to 
the non-generation of forms that fail of propagating, and segregate with 
reference to the generation of forms that propagate successfully, but 
separately. 
Adaptational selection is exclusive generation that depends upon supe- 
rior adaptation either to the environment or to other members of the 
same species. 
Nutural selection is the exclusive generation of those better fitted to 
the natural environment, resulting from the failure to generate of those 
less fitted. 
Artificial selection is the exclusive generation of those better fitted to 
the rational environment. 
Reflexive selection is the exclusive generation of those better fitted to 
the relations in which the members of the same species stand to each 
other. Sexual, social, and institutional selection are forms of reflexive 
selection. 
The environment is nature lying outside of the inter-generant. The 
influence of the environment is the sum of the influences that fall upon 
