VARIATION OF POLAR REACTION 277 



reaction depends on the age of the specimen. A moderately 

 young specimen gives higher type of reaction than one 

 which is very young or one which is old. 



On account of modification of the tissue, its excitability 

 to anode-break undergoes progressive diminution. In 

 consequence of this, modified types of reaction Km Am 

 and Km Kb Am are sometimes found to occur in Mimosa. 



The polar reactions in Protozoa are not exceptional. 

 Similar effects are observed in Mimosa under specific 

 conditions. 



