20 
BULLETIN 56, HAWAII EXPERIMENT STATION 
In all instances the sucrose suddenly increased upon reaching the 
rootstock and the hexoses correspondingly decreased. This fact fur- 
ther confirms the conclusion that inversion of sucrose to hexoses is pri- 
marily for the purpose of translocation. The hexoses again decreased 
rapidly toward the basal part of the rootstock. They were seldom 
entirely wanting, and were found in smallest quantity in regions where 
translocation was at a minimum and, likewise, in greatest quantity 
where it was at a maximum, confirming the opinion that they prac- 
tically alone effect translocation. In the basal part of the rootstock 
sucrose decreases, of course, as the result of its condensation into 
starch. The occurrence of sucrose in very appreciable quantities in 
the rootstock, regardless of age, suggests that it is essentially intra- 
cellular, the true intermediate product between the hexoses and starch, 
and in some sort of equilibrium with the latter. 
The hexoses are abundantly present in both young, and the apical 
part of old, rootstocks as compared with the basal part of old root- 
stocks, a fact offering 
further evidence that 
reducing sugars are al- 
ways associated with 
growth . This bears o ut 
the observation of Colin 
with the sugar beet (4) 
that the hexoses are 
always found at the 
growing points. 
The finding of starch 
in various parts of the 
stems of hill 3, together 
with a very low per- 
centage of starch in the 
rootstock, .whereas 
starch was found only 
in negligible quantities 
in the stem of the older 
Fig.15.— Sugars in different parts of the plant hills is in aCCOrd with 
the observations of Davis, Daish, and Sawyer (6), who showed that 
starch forms in the leaves of the mangel plant only during its very 
early growth. In explanation of this phenomenon they advanced 
the hypothesis that starch was stored in the leaves because the root 
of the mangel had not yet developed, but that as soon as sugar began 
to be deposited in it the starch disappeared from the leaves and did 
not reappear. 
VARIATIONS IN THE SAME HILL 
A number of hills of different ages were classified and genealogized 
in the usual manner to correlate the variations taking place in the 
composition of the plants with the growth of the hill in the field. 
Representative plants from each generation were selected for deter- 
mination of their sugars and some other constituents. Table 7 gives 
the results of the analysis of the stem 7 and the rootstock. 
SHCATHS 
eooTsroc/r eoorsroc/c 
s4P/Cs4L Ps4/er B/IS/IL P^GT 
7 The term "stem" is here used to include the sheaths and the stem proper, the leaves and the midribs 
being discarded. To obviate the possibility of includiug a part of the stem with the rootstock, and vice 
versa, a section of the apical part of the rootstock and the lower part of the stem, about 2 inches, was 
discarded. 
