

VITALITY AND GERMINATION OE SEEDS. 247 



that the action is the same all over the root and by using 

 a solution considerably diluted and restricting the time of 

 immersion as much as possible, one is able to obtain 

 radicles having only the outer layer or two browned and 

 yet this is sufficient to obtain the results mentioned above. 

 The permanganate method of measuring and estimating 

 the growth and curvature of radicles is however more 

 suitable for general experiments, class demonstrations, 

 etc., than for accurate detailed experimentation. A good 

 specimen will shew the various phenomena of growth in 

 length and curvature. It will shew very plainly the 

 endogenous origin of secondary roots, these appearing as 

 little white prominences burrowing through the outer 

 browned cortical tissue and in addition the specimen may 

 be preserved in spirit as a permanent preparation. 



