752 Fluctuations 



the result is due to the one, and what to the 

 other factor. 



The scientist, on the contrary, has nothing to 

 do with the industrial product. His task is the 

 analysis of the methods, in order to reach a 

 clear appreciation of the influence of all the 

 competing factors. This study of the working 

 causes leads to a better understanding of the 

 practical processes, and may become the basis 

 of improvement in methods. 



Starting from these considerations, we will 

 now give some illustrative examples, and for 

 the first, choose one in which hybridization is 

 almost completely excluded. 



Sugar-canes have long been considered to be 

 plants without seed. Their numerous varieties 

 are propagated only in a vegetative way. The 

 stems are cut into pieces, each bearing one 

 or two or more nodes with their buds. An 

 entire variety, though it may be cultivated in 

 large districts and even in various countries, be- 

 haves with respect to variability as a single in- 

 dividual. Its fluctuability has been limited to 

 the earliest period of its life, when it arose 

 from an unknown seed. The personal charac- 

 ters that have been stamped on this one seed, 

 partly by its descent, and partly in the develop- 

 ment of its germ during the period of ripening, 

 have become the indelible characters of the va- 



