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Äs to the arragments of the experiments in* the 
field the seeds of each isolated plant should he sown as 
usual in one single little parcel — the quantity of seeds 
is not large, as a rule. Standard parcel are put in the row 
at certain distances from each other. The rot resistance 
of the standard variety should be perfectly known; it 
ought to be as homogenous and as highly improved as 
possible, of course. 
If only a few roots are at hand the taking of the 
proofs for the analysis is best made by borings in the 
roots. The bored roots may be preserved if the bore- 
holes are covered with sublimated sulphur. This prevents 
infection in the injured spots, which certainly is of great 
importance. Jekelius has shown that injured roots in- 
vert the cane-sugar more easily than the intact. The 
same method is used when selection of roots is made 
from a population. When a large number of roots is 
at hand it may be convenient to take out an average 
proof, and then to saw the roots. This latter method 
has the advantage that the number of analyses is con- 
siderably diminished, and the whole procedure takes 
shorter time. It is impossible, on the contrary, to make 
any selection whithin the pedigree, which may be wan- 
ted especially after the first selection. 
The extraction of the pulp obtained by the borings 
or sawing may conveniently be done by the method 
used in the root-laboratories, viz. by extracting with cold 
water, following the method of Krüger. It is neces- 
sary to precipitate the lead with soda, however. 
As it is a question of being able to analyze some 
hundreds or some thousands of roots great emphasis 
should be laid upon the possibility of making the ana- 
lyses rapidly. The method of analysis, which I have 
used in my purely theoretical study, viz. the reduction 
of Fehling’s solution, is quite impractical as it calls for 
quite too long a time. Only about 5 — 10 analyses can be 
