176 THE DOCTRINE OF DESCENT. 
abode to a new and strange environment, after a longer 
or shorter effort of the organism to domesticate itself, 
either die out, or else accommodate themselves to the. 
new conditions and become acclimatized. Every accli- 
matization is thercfore an adaptation, acconipanied by 
modifications more or lcss perceptible. Thus, in consc- 
quence of the varied conditions of life, there is a wide 
divergence among races of men who, by their kindred 
language, are of the same origin, not to mention those 
whose relations linguistic inquiry has not yet decided. 
How different is the idiosyncrasy of the Englishman 
from that of the Hindoo! Physically and psychically, 
they represent two remarkable sub-races of which the pe- 
culiarities must be ascribed to adaptation,—in the latter, 
to a climate which requires a vegetable diet, and, eliciting 
neither bodily nor mental energy, favours a dreamy 
sensuality ; in the former, to a country which is in every 
particular the opposite of the Indian original home. 
Similarly, the annual alternation in the vital phenomena 
of so many organisms, designated as hybernating ani- 
mals, is a case of adaptation. It is changed the moment 
the organism is exposed to another climate, or rather 
acclimatization is essentially the accommodation of the 
hybernating animals to the new climate. 
In all these examples we have the results of direct 
adaptation, in which the power of resistance in the 
individual comes into play, as does cumulative adapt- 
ation in artificial, and the survival of the fittest in 
natural, selection. In all cases of adaptation, one or 
several organs are primarily concerned, either actively 
or passively; and only in consequence of the resulting 
modifications are the other organs drawn into sym- 
