Current Investigations in Economic Botany, 109 
canes raised from a series of selected cuttings shall be grown under 
exactly similar conditions, otherwise it is impossible to deduce any 
reliable conclusions from differences found in the second generation, 
which might be the result of the selection practised or due to 
differences in environment, mode of treatment, period of cutting or 
other factors the exact result of each of which it would be imposible 
to distinguish. 
The earliest experiments in chemical selection of sugar canes 
appear to have been made by Thompson and Edson, at Calumet 
Plantation, Louisiana, in 1890 to 1892. They first ascertained by a 
series of tests that if a cape was cut transversely into four equal 
portions, the juice of the third portion, counting from the base, 
represented in its composition the average of the juice from the 
cane as a whole. A number of canes were taken, the juice 
from the portion indicated of each analysed. Two groups of canes 
were selected, (a) those richest in sucrose—the “high canes,” 
(b) those poorest in sucrose—the “low canes,” and ordinary 
cuttings from the upper parts of these canes were planted. The 
following year the canes grown from the cuttings were reaped and 
analysed, and the results may be tabulated as follows:— 
Planted 1890. 
Reaped 1891. 
Average of Sucrose 
Average of Suer 
per cent. 
per cent. 
High Canes .. 
14-7 
11-2 
Low „ 
11-9 
10-9 
Very similar experiments have been made by Bovell and 
Harrison, and Bovell and d’Albuquerque in Barbados, Borame in 
Mauritius and Watts in Antigua. The work of Watts affords the 
most recent results and accordingly it will be convenient to sum¬ 
marize this. Watts’ experiments have been continued over four 
years, and have consisted in selecting a series of “high” and “low” 
canes respectively. Each year the ten richest individual canes from 
the “ high ” plot have been taken and the ten poorest from the 
“ low ” plot and three cuttings from each planted out to furnish the 
crop of the succeeding season, and as the result of the growth of 
these cuttings, there have usually been about 100 to 150 canes 
suitable for examination in each annual series. Canes of less than 
ten internodes are rejected, and of each of the others the portion 
below the middle of the fifth internode from the base is cut off and 
the composition of the juice ascertained. 
