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SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 87 



Fig. 6. — Carbon dioxide-assimilation curves derived from Figure 4. 



Ordinates, carbon dioxide assimilated. Multiply by 0.025 to obtain cubic 



centimeters per minute. 

 Abscissas, carbon dioxide concentration. Multiply by 0.000041 to obtain 



volume per cent. 

 Parameters, ligbt intensities. Multiply by 3.56 X 10"* to obtain 



watts/cml Multiply by 4.96 to obtain foot-candles. 



Fig. 7. — Carbon dioxide-assimilation curves from second experiment. 



Ordinates, carbon dioxide assimilated. Multiply by 0.025 to obtain cubic 



centimeters per minute. 

 Abscissas, carbon dioxide concentration. Multiply by 0.000041 to obtain 



volume per cent. 

 Parameters, light intensities. Multiply by 3.56 X lu"* to obtain 



watts/cm'. Multiply by 4.96 to obtain foot-candles. 



