ACQUIRED ADAPTATIONS 445 
similarly responding, and if each generation were influenced 
ever so little by the responses of the generations before, 
that is to say, if the acquired peculiarities were inherited: 
to any extent, the foundations laid by the pioneers would be 
built upon by their descendants. As a result we should 
have in successive generations the stems growing longer, 
and the leaves more branched and finally becoming com- 
pound. An increased sensitiveness to light might be accom- 
panied by greater sensitiveness to contact and this might 
lead to a coiling of the leaf-stalks around neighboring twigs, 
thus establishing the habit of climbing by means of which 
better exposure to light would be most economically secured 
through utilizing for support the very bushes which had 
made the shade. As a consequence of the starving out of 
the upper ovules there would result finally a fruit the upper 
part of which had become a mere tail-like projection sur- 
mounting a one-sided indehiscent base. A general hairiness 
which had been developed in all the exposed parts of the 
plant in response to the dryness of its new environment 
might especially affect the fruit as being now especially ex- 
posed, and might lead even to an elongation of the tail which 
would thereby become well adapted for enabling the wind 
to carry the precious seed high over surrounding shrubbery. 
In some such way as this it is conceivable that the characters 
of a clematis may have evolved. 
The first naturalist to suggest that organisms had evolved 
through the accumulation of acquired characters was Jean 
Baptiste Lamarck, of France, who flourished in the early 
part of the nineteenth century. His doctrine is called La- 
marckism, or as modified by his more recent followers, Neo- 
Lamarckism. Lamarckians have advanced much evidence 
to show that acquired characters are often adaptive and may 
be inherited; but while most naturalists might concede the 
possibility of such characters being now and then adaptive, 
the great majority of evolutionists have remained uncon- 
vinced that acquired characters are ever fixed by inheritance. 
So far as we know, acquired characters do not long survive 
the conditions under which they arise. Cultivated plants 
escaped from cultivation soon become, as we have seen, 
