] 
1 
4 
; 
279 
These surmises illustrate what may be supposed to be 
accomplished in the differentiation of species by the trans- 
mission of developmental variations in accordance with the law 
of earlier inheritance. Further consideration will shew that, if 
some members of a species acquire, on account of environment, 
habits necessitating the increased use of one part, and other 
members acquire other habits with different results, and so on, 
there would, in course of time, arise from one original stock 
two or more species very different to each other or to the 
parent form—simply because their small initial differences had 
been constantly increased by the action of the law of earlier 
inheritance. 
m2 
