ELECTROKINETICS 389 



graphic relationships. In Fig. 1655, the curves of two species 

 and two varieties which are known to be of close relationship; 

 all four have similar migration curves and practically identical 

 isoelectric points; each was found to have 28 chromosomes. 

 E. heterophijlla (Fig. 1655) was shown by its latex behavior to 

 be an isolated species; it was found to have 56 chromosomes. 



The discoveries of Landsteiner, Mez, Moyer, and Svedberg 

 are among those pioneer contributions in which biological 

 phenomena, heretofore little understood, are shown to rest upon 

 readily determinable physical and chemical properties. Mobihty 

 curves and isoelectric points are not the recognized bases of 

 species classification, but they indicate kinship as much as do 

 flower structure, facial characteristics, and hke criteria of racial 

 grouping. 



