W. A. Davis and G. C. Hawyer 



371 



falls considerably from G a.m. to 2 p.m., owing to the smallness of the 

 laevulose values. 



In the potato stalks, the fluctuations of the "apparent laevulose"' 

 are far less than in the mangold stalks (compare Fig. 2 with Figs. 7, 

 8 and 9 in preceding paper I), whilst the ratio of hexoses to saccharose 

 remains nearly constant (see Table II) throughout the 24 hours. The 

 variation of "apparent" dextrose and "apparent" laevulose is discussed 

 later (see p. 373). 



Fig. 2. Potato stalks, July 10-17, 1914, 



The fact that in the leaf the saccharose is always greatly in excess 



I s 

 of the hexoses (ratio ^-'- varies from 0-08 to 0-45) whereas in the stalks 

 c.s. ' 



I s 

 the hexoses are always greatly in excess of the saccharose (ratio '-^ 



Co. 



