378 



BOTANICAL GAZETTE 



[may 



TABLE XI 

 Water intake in Xanthium seeds 



Intake 



percentage 



9 m 5 



J m 7-5 



y=io 



y=i5 



y=2o 



V=25 



5' 



Velocity in 



percentage 



per hour 



10.1705 

 9.0322 

 8.0214 

 6.3264 

 4 . 9896 



3.9351 



Logarithm 



I.007342 



0.955794 

 0.904250 



O.801157 



O . 698066 



o • 594956 



20" 



Velocity in 



percentage 



per hour 



19.0894 



I7-3838 

 15.8304 



131278 



10.8866 



9.0280 



Logarithm 



I . 280792 



I . 240145 

 I. 199492 

 1.118191 



I.036893 

 0.955592 



35" 



Velocity in 



percentage 



per hour 



32 



3° 



28 



24 

 20 



17 



8097 

 3700 

 1116 

 0865 

 6376 

 6826 



Logarithm 



I.516002 



I.48244S 

 I . 448886 



I. 381774 



I.3H659 

 I . 247546 



In the later work the velocity calculated from the tangents is 

 expressed in percentage per minute, instead of percentage per 

 hour. The velocities for the same six points, on the curves shown 

 in tables IX and X, are given in table XII. 



TABLE XII 

 Water intake in Xanthium seeds 



Intake 

 percentage 



y- 7-5 



y~io. . 



y=2o. . 

 y=2 5 .. 



5 



20 



Velocity in 

 percentage 

 per minute 



O.27122 

 O.18134 

 O.12589 

 O.09066 

 O.06537 

 O.05722 



Log M Velocity 



1.433322 

 I . 258494 

 I .099992 

 2.957416 



2.815378 

 2.757548 



Velocity in 

 percentage 

 per minute 



O.64872 

 O.50920 



o . 39968 



O.24624 



o. 19096 



O.15611 



35 



Log» Velocity 



Velocity in 

 percentage 

 per minute 



1. 81 2057 

 I . 706888 

 I. 601 702 



i- 391358 

 1 . 280943 



1. 19343 1 



Log M Velocity 



1. 17576 



0.99707 

 0.84554 



o . 60806 



0.44820 



0.38284 



0.070318 



1.998726 

 I. 927134 



1.783947 



I. 651472 



x. 583018 



Temperature 



— Having now obtained 



points 



mine the quantitative effects of temperature on the rate of moisture 

 intake. First we must know the ratio of the velocity at 20 to that 



to that at 20 C. These ratios 



of 5° 



the 



the intake velocities presented in tables XI 



table XIII. 



average velocity at 5 



XI 



unitj 



velocities at 20 and 35 C. according to the ratio 1:2.05: 2. ttfX 



I -83 = 3-75- 



intake in the last curve 



