POTATO BEEEDING AND SELECTION. 23 
produce the best plant) for now fourteen years. My main object here has been absolute 
freedom from disease, and these potatoes are now descended from a line of single tubers, 
each the best plant of the year and absolutely healthy; and concurrently with the 
endeavor to wipe out all hereditary tendency to disease, I have always kept in full 
view the point of increasing productiveness. The result may be thus shortly stated: 
Dividing the first twelve years into three periods, the average number of tubers upon 
the annual best plant selected was, for the first period of four years, 16; for the second 
period of four years, 19; for the last period of four years, 27; or nearly double the 
number produced during the first series of four years. And if, as I might very 
fairly have done, I had confined the first period to the first three years (instead of four), 
the last period would have shown an average of 27 tubers against 13 in the first period, 
or more than double. 
The care with which this experiment was apparently conducted 
and the selection of the strongest, most disease-free, and productive 
plants would seem to indicate that Hallet, at least, had a very clear 
conception of the advantages of selection in building up vigorous 
and productive strains of potatoes. 
Carrier e says: 1 
The potato furnished us with examples of modifications just as remarkable as those 
which we have reported for beans and for corn. . . . Every year, in reality, when 
we harvest the tubers and wish to conserve the purity of the variety, we are obliged 
to purify, that is to make a choice and reject those which, as we say, have degener- 
ated. . . . The modifications in the potato may occur equally well in the underground 
parts; that is what has happened in the variety called Pousse-debout. The name 
Pousse-debout has been given to this variety because the tubers which it produces, 
instead of being placed flat, or nearly so, in the soil, are arranged one against the 
other, much like pieces of wood are disposed for transformation into charcoal. 
It is further stated that the Marjolin potato is a variety possessing 
the peculiar quality of never flowering and of being very early, but 
notwithstanding this fact it is continually producing plants which 
flower and produce seed, and which, owing to this fact, are not as 
early as the parent plant. In yet another variety, the Chardon, 
Carriere observed transformations in color of flowers, shape of tubers, 
and season of ripening, and this, too, in a strain which had been under 
observation for a long time without having previously shown any 
variation whatsoever. 
GoiTs 2 experiments in 1884 and 1885 demonstrated that tubers 
from productive plants gave larger yields than tubers from unpro- 
ductive plants, the total gain being a little more than 24 per cent. 
In 1897 Fischer 3 began some selection work with the potato, in 
which variations in productiveness, shape, and starch content of 
1 Carriere, E. A. Production et Fixation des Varietes dans les Wge"taux, 72 p., illus. Paris, 1865. (See 
p. 40-41.) 
2 Goff , E. S. Experiments with tubers taken from productive and unproductive hills. N. Y. (Geneva) 
Agr. Exp. Sta., 3d Ann. Rpt., 1884, p. 301-305, Albany, 1885; 4th Ann. Rpt., 1885, p. 232-235, Albany, 1886. 
(A copy of this 4th Rept. was published also at Rochester. In this copy the reference will be found on p. 
204-207.) 
3 Fischer, Max. Kartoffelzuchtungs- und Anbauversuche. In Fiihling's Landw. Ztg., Jahrg. 49, 1900. 
Heft 8, p. 301-307; Heft 9, p. 343-352; Heft 10, p. 369-372. 
