200 STUDIES IN PLANT REGENERATION 
of 18 mm. had three healthy shoots already considerably advanced 
in development, they nevertheless gave rise to additional buds as 
outgrowths from the cambium (Fig. 1). Beyerinck * as well 
Fic. 1, Root-cutting of Кода Armoracia showing a shoot regenerated from the 
cambium of the lower surface, besides lateral shoots developed from preformed buds 
on the rin 
as Rechinger stated that no regeneration takes place when the 
primary rind is cut away. The following experiment shows that 
this is not necessarily the case. 
Experiment 2.-- From a number of roots of horseradish, 
the rind, cortex, and cambium layer were removed. Тһе part 
left, consisting of only the fundamental tissue and the bundles 
which are scattered through this, was cut up into slices averaging 
20 mm. in height and 12 mm. in diameter. After four weeks 
shoots developed in the neighborhood of the scattered bundles 
and more often at the distal end than at the proximal (Fig. 2). A 
callus of a few layers of cells preceded the formation of the shoot. 
In this case, therefore, the root can actually regenerate, in addi- 
* Beyerinck, M. W, 
und Nebenwurzel, 52. 
Beobachtungen und Betrachtungen iiber Wurzelknospen 
