282 BOTANICAL GAZETTE [SEPTEMBER 
and aspartic acid give a dextro-rotation which is increased by acids, while 
asparagine gives either dextro- or laevo-rotation accordingly as the solution is 
or is not acid. In the mangold and sugar beet there is an apparent excess of 
dextrose over levulose which is due to the presence of glutamine, while in snow- 
drop, tropaeolum, and potato the presence of asparagine results in an apparent 
s 
transfer of the impurity; in the leaves the dextrose-levulose ratio is in the 
neighborhood of unity; in the midribs and stalks it ranges from 2.5 to 10.0. 
The pentoses which are present in the alcoholic extract also affect the readings. 
The author determined the proportions of the two sugars present in the 
three series discussed in the preceding paper, using the methods there employed. 
In the early morning there was found in young leaves a dextro-rotation still 
greater than that which would be observed if all the sugar present were dextrose. 
In older leaves there appeared to be a steady formation of a laevo-rotatory 
substance and a gradual transformation into a compound having still greater 
laevo-rotation. The author considers that this is manufacture of asparagine 
and transformation into aspartic acid. Both in the second and the third series 
there are three rises and three falls in the amount of apparent dextrose in 24 
hours, this fact pointing to a regular and rhythmical variation in the rate of 
production of the optically active impurities. 
The character of the optically active impurities in the upper portions of 
the stalks is quite different from that in the lower portions, as shown by the 
fact that when determinations of the sugars in the lower portions of the stalks 
are made simultaneously by polarization and reduction methods the polariza- 
tion results are 4o per cent higher than those obtained by reduction, while on 
the upper portion of the same stalks the results by polarization are 85 per cent 
lower than the reduction figures. Hence the optically active substances inter- 
fering with the polarization are quite different in the two portions of the stalk, 
suggesting the optical behavior of d- and ]-asparagine and d- and 1-glutamine. 
Furthermore, there are two different optically active substances at different 
times during the 24 hours. For all these reasons we can at present obtain no 
true values for these sugars, and there is at least nothing to disprove the 
assumption that dextrose and levulose exist in the leaves and stalks as invert 
sugar, travel in approximately equal amounts to the roots, and there undergo 
recombination into saccharose. 
In the third paper of the series Davis and SAWYER have e applied similar 
yeasts were made. eae the authors consider that BRowN and Morris were 
