344 



THE FOOD OF PLANTS 



100 





 10 



CO 



so 



40 

 3O 

 ZO 

 iO 

 O 



a. 



S 



1) 



b 







660 



\L 



> 



/\ 



r ~~ " -- . 



\ 



I/ 



Als.Bed 



A. 



Ai 



Orange 



ffSff 



600 



62- 



FeZ/ow 



58 



Green 



SO 



Blue 



'fff 



s. Green 



. Green 



s. Bed 



r 



7 leaves 

 ifc. Sol it. 



a/ B 



D Eb F 



FIG. si. 



a, JB 



.-gr. 



Oraiifji- 



Yd/oic 



Blue 



FIG. 52. 



FIGS. 51, 52. Curve 01 absorption (Abs.') and primary assimilation (Ass.) in sun spectrum, after Engelmann, 

 Bot. Zeitutig, '1884, Taf. II. The ordinate for tlie maximal assimilation =100. Fig. 51 gives the curves for green 

 chloroplastids (Ass. Green and Abs. Green), and for red algae (Florideae) (Abs. Red and Ass. Red], and Fig. 52 

 for a blue-green alga (Oscillaria) (Ass. Bl.-gr.n-nA Abs. Bl.-gr.\ The curve En. gives the distribution of energy 

 in the spectrum, after Langley t Annal. d. chira. et d. phys., 1882, v. ser., T. XXV, p. 212 ; cf. also Engelmann, 1. c., 

 p. 102). The median figure is after Reinke (Bot. Zcitung, 1884, p. 59, and PI. I', and gives the absorption spectra of 

 two and of seven superposed leaves (2 leaves and 7 leaves] as well as of an alcoholic solution (Ale. Sol.) of leaves of 

 hnftaticns parviflora. 



