96 



PRINCIPLES OF PLANT-TERATOLOGY. 



doubtless to be ascribed to an abnormal flow of nutri- 

 ment into the organ or organs concerned." 



Yet it seems fairly clear that the environmental 

 factor is not the only one involved ; for f asciated stems 

 appear as isolated cases amongst others which are 



Fig. 27. — Phaseolus multiflorus. Axillary shoots (fasciated at base) 

 formed after excision of plumule (ep.). as, axillary shoots; cot, 

 cotyledons. (Semi-diagrammatic.) 



perfectly normal and where both are growing 

 apparently under precisely similar conditions. It 

 would appear, therefore, that the idiosyncrasy of the 

 individual organ or plant itself is another, if not the 

 chief factor, which must not be left out of considera- 

 tion. Variability of constitution causes variability of 

 reaction to the environment. 



