COMPOSITION ttf SUCCESSIVE STAGES. 239 



diminishes in quantity, being, perhaps, replaced by 

 magnesium. 



As to potassium, no transfer is fairly indicated, except 

 from the ears. These contained at blossoming (Period 

 III) a maximum of potassium. During their subsequent 

 growth the amount of this element diminished, being 

 probably displaced by magnesium. 



The data furnished by Arendt's analyses, while they 

 indicate a transfer of matters in the cases just named, 

 and in most of them with great certainty, do not and 

 cannot from their nature disprove the fact of other simi- 

 lar changes, and cannot fix the real limits of the move- 

 ments which they point out. 



