Xo. 529] 



ORGANIC RESPONSE 



35 



ontogenetic procedure of the plantlet will be much like 

 that of a seedling. 



The exact observation of the manner in which environic 

 effects may pass the regeneration stage and reappear 

 has not yet been made to any great extent. Doubtless 

 many conditions will be found to affect the process. 

 Bud sports, or vegetative mutations, are, of course, fully 

 transmissible along a series of stages of division by 

 cuttings, and many of them have been found to trans- 

 mit their divergent characters by seed resulting from 

 close pollination. Mechanically considered, the vegeta- 

 tive reproduction of a plant consists simply of its per- 

 petuation through an unbroken chain of metameres or 

 internodes, each joint arising from a growing point borne 

 terminally or laterally by its predecessor. The projec- 

 tion of induced characters formed by metamere A into 

 metamere B, therefore, involves the question of germ- 

 plasm as represented by the embryonic mass of the grow- 

 ing points with no opportunity for carrying over struc- 

 tures mechanically as in the Paramecium. The compar- 

 ative action in heredity when plants are transported to 

 new climates through bulbs and tubers and through seeds 

 is one that has not yet been made although doubtless hor- 

 ticultural and agricultural literature is rich in the records 

 of facts upon which decisive generalizations might be 

 made. 



The genetic character of environic effects remains to 

 be considered. In any species or genotype there is, 

 withal, a limited number of things included within the 

 morphological possibilities. The appearance of any char- 

 acter in an acclimatization culture raises a question 

 at once as to the standing of the new feature. Is it a 

 regressive character, once displayed by the species and 

 now recalled by the very conditions under which it was 

 first induced, or is it to be considered as a character de 

 novo, arising simply and directly in response to the ex- 

 ternal agencies which have been seen to induce it? Thus 

 in the results cited above, our general knowledge of the 

 Cactaceae leads us to assert with some confidence that the 

 reappearance of a full complement of spines in a prickly 



