14 



BURTON EDWARD LIVINGSTON 



that this is true for both leaf surfaces and for their averages, 

 which represent the whole leaf. While the indices were 0.018 

 for the upper and 0.005 for the lower leaf surface at the end of 

 hour 21, the former index increases to 0.081 at the end of hour 8 

 and the latter to 0.120 at the end of hour 12. The index of the 

 leaf as a whole, on the basis of the actual times of observation, 

 varies from 0.0115 (hour 21) to 0.0960 (hour 12). The order of 



TABLE 2 



Index of Transpiring Power, Phtsalis 





UPPER LEAF SURFACE 



LOWER LEAF SURFACE 



ENTIRE LE.VF SURFACE 



HOUR 



At end 

 of hour 



For preceding 

 hour 



At end 

 of hour 



For preceding 

 hour 



At end 

 of hour 



For preceding 

 hour 



Actual 



Relative 

 to hour 1 



Actual 



a 



t 

 "a 

 p: 



to hour 1 



Actual 



|r 

 5 2 



ly 25) 





































21 



0 



018 











0 



005 











0 



0115 









22 . 



0 



021 



0 



0195 



0 



89 



0 



012 



0 



0085 



0 



65 



0 



0165 



0 



0140 



0 80 



23 



0 



024 



0 



0225 



1 



02 



0 



009 



0 



0105 



0 



81 



0 



0165 



0 



0165 



0.94 



24 



0 



023 



0 



0235 



1 



07 



0 



015 



0 



0120 



0 



92 



0 



0190 



0 



0178 



1.02 



Iv 26) 





































1 



I 



021 



0 



0220 



1 



00 



0 



Oil 



0 



0130 



1 



00 



0 



0160 



0 



0175 



1.00 



2 





023 



0 



0220 



1 



00 



0 



018 



0 



0145 



1 



12 



0 



0205 



0 



0182 



1.04 



3 



0 



035 



0 



0290 



1 



32 



0 



020 



0 



0190 



1 



46 



0 



0275 



0 



0240 



1 37 



4 



0 



025 



0 



0300 



1 



36 



0 



025 



0 



0225 



1 



73 



0 



0250 



0 



0263 



1 . 55 



5 



0 



025 



0 



0250 



1 



14 



0 



063 



0 



0440 



3 



38 



0 



0440 



0 



0345 



1.97 



6 



0 



036 



0 



0305 



1 



39 



0 



070 



0 



0665 



5 



11 



0 



0530 



0 



0485 



2.77 



7 



0 



040 



0 



0380 



1 



73 



0 



060 



0 



06.50 



5 



00 



0 



0500 



0 



0515 



2.94 



8 



0 



081 



0 



0605 



2 



75 



0 



089 



0 



0745 



5 



73 



0 



0850 



0 



0675 



3.86 



9 



0 



067 



0 



0740 



3 



36 



0 



078 



0 



0835 



6 



42 



0 



0725 



0 



0788 



4.50 



10 



0 



062 



0 



0645 



2 



96 



0 



087 



0 



0825 



6 



34 



0 



0745 



0 



0735 



4.20 



11 



0 



072 



0 



0670 



3 



05 



0 



103 



0 



0950 



7 



31 



0 



0875 



0 



0810 



4.63 



12 



0 



072 



0 



0720 



3 



27 



0 



120 



0 



1115 



8 



58 



0 



09ro 



0 



0918 



5.24 



occurrence of the variations will be considered later, as will also 

 the range of the average condition for the hour period; attention 

 is best confined here to the degree of variation and its meaning. 

 It will be recalled that the index under consideration is, in each 

 case, the quotient obtained by dividing the time necessarj' for 

 the paper response in the water test by the corresponding time 

 required for this response on the leaf surface. Since the cobalt 



