296 STUDIES IN PLANT REGENERATION 
$ Фф Experiment 47. — Bean flowers on their pedicels were placed 
in the frame beside the half-mature pods. Тһе former always died 
without regeneration, while the pods rooted easily. Тһе difference 
is doubtless to be ascribed to the smaller amount of material avail- 
able for regeneration in the flower than in the fruit. 
Experiment 48. — When the pedicel is cut off, or pulled off, 
and the pod alone is planted, it succeeds in forming a small callus, 
but no roots. There is, however, little doubt that such a part 
has the power of producing roots and that better manipulation 
will make this manifest. 
* 
The foregoing experiments have demonstrated that every part 
of the plant, even when preformed rudiments are absent, has some 
power of regeneration, though in a majority of the cases this is not 
complete enough to establish a new plant. One fact, furthermore, 
is brought into undoubted prominence as a result of the experi- 
ments, with so few exceptions that these are practically negligible. 
This is, that the disposition for root-formation is much more wide- 
spread throughout the plant and more easily energized than the 
power to produce shoots, Тһе proportion of parts which formed 
only roots to those in which both sets of organs were regenerated 
was as 74:20. It has been seen, too, that where both kinds are 
produced, the roots usually precede the shoots by a period of time 
varying from three weeks to seven months. Only three instances 
were found in which the cuttings regenerated shoots alone — the 
potato-tuber, the central tissue of the horseradish-root and the 
hyacinth bulb-scale. In а certain sense, however, even these parts 
might be said to share in the production of roots, for the regen- 
erated shoots almost immediately after they themselves become 
visible, form root primordia, Оп the very youngest buds of the 
potato these are present, and become developed before the shoot 
is further differentiated. The converse has never proved true in 
these investigations.* In the case of the Pelargonium leaf-cutting 
(Exp. 13) a shoot did spring from the root. However, this shoot 
was not the first one formed ; it appeared only after a lapse of seven 
months and as the result of a second injury. An attempt at an 
* Though Vóchting and Beyerinck state that it is often the case in woody roots of 
ees. 
