88 



A MONTANE RAIN-FOREST. 



surfaces of the leaves of one plant were coated with molten cocoa butter, 

 the under surfaces of the second were so coated, and the third was 

 left uncoated as a control. In this condition the three plants were 

 again run through one day. It was only after the completion of such 

 a series, the determination of the leaf areas, and the calculation of 

 the results that it was possible to know how evenly matched the rates 

 of the three plants were before coating, and this made necessary such 

 liberal discarding of results that only two such experiments were found 

 to be as satisfactory as might be desired (see tables 22 and 33). 



1.50 



2.00 



1.50 



1.00 



i.oo 



i '' \ V 



/IV V 



/ ' * V 



c / 



// 



\ -x 



\/ 



Unc 

 LSC 



IN 

 /\\ 



\ \ 



/ 



\/ 



G A. M- 8 



s Hi; AM. s 



FIG. 13. Normal daily march of transpiration for three plants of Pilea, 

 and march for same plants on succeeding day after leaves of C had 

 been coated on upper surface (USC), those of A had been coated on 

 lower surface (LSC), and those of B had been left uncoated (Unc) 

 as a control. Suspended curve is concurrent evaporation, plotted 



to one-fourth of scale ( -. ) . 



