miscellaneous: stimuli underlying tumor-formation 547 



Fig. 412.^ — Vertical section through the hyperplasia! region shown on Fig. 

 411. St, stomata. Cortex full of starch grains. The pith was also full. Photo- 

 micrograph by the writer from a free-hand section mounted in water. 16 mm. 

 obj., 4 oc, bellows at 35. 



