miscellaneous: stimuli underlying tumor-formation 533 



Fig. 401. — Bhtck ol' i)aixM| «tenle ]j(it;ito fie^li e,\i)o:sed to same light, temperature 

 and atmosphere as Fig. 4U0 and in all respects like it, except that the lower 

 hyperplasias have fused and ruptured encircling the entire base of the shoot. 

 Photographed April 10. X 5. 



