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THE AMERICAN NATURALIST [Vol. LIII 



Summary 



1. The number of flowers in each head is greatest for 

 the terminal heads of each cyme. 



2. Otherwise the number of flowers in each head is rela- 

 tively constant for each individual plant. 



3. There is a great variation between individuals but, 

 in those plants with numerous heads, the mode falls on 

 or near one of the main or secondary numbers of the 

 Fibonacci serie^. 



