MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 65 



lOrom<= 

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20mm-- 



lOmm. - 

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20 



m.m- 



lOmm 



5mm 



20mm-- 



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-I I L. 



2 4 6 8 10 12 2 4 6 8 10 12 

 P.M A.M. 



2 4 6 8 10 12 2 4 6 8 10 12 



P.M. 



A.M. 



Fig. 19. Curve of growth of scape of Arisaema triphyllum under normal illumi- 

 nation, March 26 to 30, 1901. (See Fig. 20.) Description on p. 67. 



