760 



THE AMERICAN NATURALIST 



[Yo-L. XL 



TABLE 2 



Constants for Variation in Seed Number in NclumUum 



Mean 24.874 ± .078 



Standard Deviation 4.339 ± .055 



Coefficient of Variation 17 . 445 ± . 1C2 



It will be noted that the distribution as a whole is quite symmetri- 

 cal. The relative variability, as measured by the coefficient of vari- 

 ation, is of the same general order of magnitude as has been found 



in plant characters by other workers. Tn order to determine whether 

 or not the variation ('.f thr <-haractcr nn<lcr consi.hM-ation follows the 

 noniuil law within tlu- limits ..f the .M'n.rs <,f ran.lcni saniplin- we 

 must cxainiiu- thr valuf> nf the analytical .-onstants, wliicli (lefine 



probable rrn.rs. I\il,.- Slu-|.i>anl's .•„ir(vti.>ns'f..r the moments 

 I find the values oivcn in Table :{. The unit for the moments is 1 

 seed. 



