Regeneration 241 



ized to some degree. This is especially true of the epidermis. In kohlrabi 

 Vochting (1908) observed that when the layer of wound cork was 

 sloughed off an epidermis had developed under it which was essentially 

 identical with that of the normal tuber and in which typical stomata 

 were present. Cells destined to be cortical in character had been radically 

 altered to form a tissue appropriate for their new position in the system. 



Fig. 9-3. Vascular strands a and b regenerating in parenchymatous tissue to connect 

 strand G with others; c, an earlier stage in this process, where procambial strands are 

 being differentiated. (From S. Simon.) 



Such reconstitution has been reported by others. The cuticle of epidermal 

 cells may also be regenerated if it has been sliced off ( Fritz, 1935 ) . 



More deeply seated tissues may be regenerated by the ^differentiation 

 of others, as is the exodermis in air roots of orchids ( Kiister, 1899; Bloch, 

 1926, 1935b) and hypodermal sclerenchyma (p. 218) in air roots of palms 

 and Araceae (Bloch, 1937, 1944). In every case these newly developed 



