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double proofs, and therefore the results may be uncer- 
tain. The anatomical structure of the roots of this 
sort may influence the results. The central cylinder in 
Gnerande is very strongly developed in comparison to 
the bark layer, and their sugar content is not the same, 
as is well known. It is possible that the proofs taken 
are no average proofs, as the short roots do not admit 
several borings to be made. The rotting of the roots 
begin in this sort in a very different manner. Some- 
times it begins in the neck of the root and proceeds 
downwards through the central cylinder. Now and then 
it is the latter one which begins to rot, while the neck 
of the root and the central cylinder are relatively sound. 
The same behaviour is found in other sorts, but I am 
under the impression that the central cylinder is very 
strong developed in all these individuals. Guerancle is 
a rather bad object for studying these questions on 
account of the nature of the central cylinder; and this 
sort will be excluded if conditions allow the conti- 
nuations of these investigations. It would be intere- 
sting, of course, to analyse the central cylinder and the 
bark layer separately and to compare these results with 
the rot resistance. 
From the above mentioned facts it is obvious that 
there are two kind of sugars in carrots, viz. cane-sugar 
and another kind, which reduces Fehling’s solution. I 
have called it invert-sugar, but I have not made any 
study to determine its real nature. According to the 
scanty statements, I have found in the literature, a quali- 
tative analysis has scarcely been made. König (1904) 
holds that besides cane-sugar also dextrose is to be 
found in carrots. Hellweg (1892) has also made sugar 
analyses of several sorts. He calculates the reducing 
sugars as invert-sugar. I think he is right, partly on 
account of the polarization-experiments made in 1917 — 
1918, where the sugar percentage of one sort was found 
