HEREDITY 
545 
ical and artificial. The protoplasm remains unaltered by 
the act of separation, reduction divisions are not involved, 
and the inheritance, except in bud-variations, is unaffected 
by the change. This is evident in those cases where the 
FIG. 404. Graft of tomato (Lycopersicum esculentum) on tobacco 
(Nicotiana tabacum). On the tomato are grafted Solatium nigrum, S. 
integrifolium, and Physalis alkekengi. Cf. Fig. 243. (Graft made by 
Mr. M. Free.) 
isolated piece is grafted upon another plant; the specific 
or varietal characteristics of the scion are seldom, if ever, 
affected by the stock. Thus, in the experiment illustrated 
in Fig. 404, a tomato stem was grafted upon a tobacco 
35 
