748 Fluctuations 



inquiry to a single individual. These curves 

 give the partial variability, and are found to 

 comply with Quetelet 's law. 



Besides this limited study, we may compare 

 the numerous individuals of one locality or of 

 a large plot of cultivated plants with one an- 

 other. In doing so, we are struck with the fact 

 that some plants have large and others small 

 fruits. We should limit ourselves to the main 

 spike of each plant, and perhaps to its lower 

 parts, so as to avoid as far as possible the im- 

 pression made by the partial fluctuations. The 

 differences remain, and are sufficient to fur- 

 nish an easy comparison with the general law. 

 In order to do this, we take from each plant a 

 definite number of capsules and measure their 

 average length. In some experiments I took 

 the twenty lowermost capsules of the main 

 spikes. In this way one average was obtained 

 for each plant, and combining these into a curve, 

 we find that the fluctuations come under Quete- 

 let 's law. Thus the individual averages, and 

 the fluctuations around them, follow the same 

 rule. The first are a measure for the whole 

 plant, the second only for its parts. 



As a general resume we can assert that, as a 

 rule, a quality is determined in some degree 

 during the earlier stages of the organism, and 

 that this determination is valid throughout its 



