Laws of Fluctuations 727 



grouping the deviations into previously fixed 

 divisions. For this purpose the variations 

 are measured by standard units, and all the in- 

 stances that fall between two limits are consid- 

 ered to constitute one group. Seeds and small 

 fruits, berries and many other organs may 

 conveniently be dealt with in tliis way. As an 

 example we take ordinary beans and select them 

 according to their size. This can be done in 

 different ways. On a small piece of board a 

 long wedge-shaped slit is made, into which seeds 

 are pushed as far as possible. The margin of 

 the wedge is calibrated in such a manner that the 

 figures indicate the width of the wedge at the 

 corresponding place. By this device the figure 

 up to which a bean is pushed at once shows its 

 length. Fractions of millimeters are neglected, 

 and the beans, after having been measured, are 

 thrown into cylindrical glasses of the same 

 width, each glass receiving only beans of equal 

 length. It is clear that by this method the 

 height to which beans fill the glasses is ap- 

 proximately a measure of their number. If now 

 the glasses are put in a row in the proper se- 

 quence, they at once exhibit the shape of a line 

 which corresponds to the law of chance. In this 

 case however, the line is drawn in a different 

 manner from the first. It is to be pointed out 

 that the glasses may be replaced by lines in- 



