Practice of Plant Breeding. 
another set (seed from 5200 feet) were only 30 inches 
high and grew 2.4 inches in the same year. 
At Adlisberg also larch-seedlings (seed from Avers 
6300 feet, and Engadine 6900 feet) were only 9 and 15 
inches high respectively. These young trees stopped 
growing on June 27th and July 2nd. 
As a control experiment, larches of the same age 
from Bonaduz seed (2350 feet) were 26 inches high, 
and went on growing till August 18th. 
Sycamores (three-year-old) from Alp Drusen seed 
lost all their leaves on October 13th and were not 
more than 16 inches, whereas others from Adlisberg 
seed were 25 inches in height and remained in leaf until 
November 12th. 
Such instances as these quite conclusively prove the 
inheritance of such habits as slow growth, time of 
growing, and of leaf-fall. Those parent larches which 
grew at 6000 feet and over had surely acquired the 
habit of slow growth simply because there was too 
short a season to grow fast. And as we have seen, this 
habit was transmitted, somehow, to their seedlings. 
The parent sycamores on Alp Drusen would certainly 
have had their leaves killed off by frost, &c., in the middle 
of October, and had transmitted the habit of shedding 
their leaves at that date to their descendants, who had 
never known a severe Alpine climate. Perhaps even 
more interesting are those experiments of Klebs, who 
was able by varying the conditions of growth to change 
the colour of Campanula trachelium from blue to white, 
and again by another change from white to blue." 
Both blue and white varieties not only of Campanulas 
but of all sorts of flowers regularly inherit the colour of 
their parents when cultivated under the same conditions. 
So that this third method, that of varying the condi- 
tions of cultivation, is quite as promising as either selec- 
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