216 THE HISTORY OF CREATION. 
this ram with normally shaped ewes, he produced a whole 
race of sheep, all of which had the qualities of the father, 
short and crooked legs and a long body. ‘ None of them 
could leap across the hedges, and they therefore were much 
liked and propagated in Massachusetts, 
A second law, which likewise belongs to the series of 
progressive transmissions, may be called the law of estab- 
lished or habitual transmission. It manifests itself in this, 
that qualities acquired by an organism during its individual 
life are the more certainly transmitted to its descendants 
the longer the causes of that change have been in action, 
and that this change becomes the more certainly the pro- 
perty of all subsequent generations the longer the cause of 
change acts upon these latter also. The quality newly 
acquired by adaptation or mutation must be established 
or constituted to a certain degree before we can cal- 
culate with any probability that it will be transmitted 
at all to the descendants. In this respect transmission re- 
sembles adaptation. The longer a newly acquired quality 
has been transmitted by inheritance, the more certainly 
will it be preserved in future generations. If, therefore, 
for example, a gardener by methodical treatment has pro- 
duced a new kind of apple, he may calculate with the 
greater certainty upon preserving the desired peculiarity 
of this sort the longer he has transmitted the same by 
inheritance. The same is clearly shown in the trans- 
mission of diseases. The longer consumption or madness 
has been hereditary in a family the deeper is the root of 
the evil, and the more probable it is that all succeeding 
generations will suffer from it. 
We may conclude the consideration of the phenomena of 
