GARDEN FLOWERS. 307 
This example gives a hint as how doubling is produced. The 
cultivation starts the variation; and continued careful selection, 
always taking seed from those most double, completes the process, 
But this continued selection and cultivation for flowers disre- 
gards the seed production, and we soon havea plant that will not 
propagate itself by seed. Having our desired plant, we must find a 
way to reproduce it. Grafting, cutting, division and layering are 
the solutions, of the problem. So, at present a large partof our 
most highly prized flower-producing plants are propagated by these 
asexual methods. ‘These methods allow of the propagation also of 
many plants which, although they may produce seeds, will not come 
true from their seeds. Seeds of such plants are sown to obtain new 
varieties, which in turn are again propagated asexually. 
Many new varieties are obtained by what is called bud-variation. 
This happens when a plant producing a certain kind of flowers 
develops a branch or branches bearing flowers differing in essential 
characteristics from the normal flowers of the plant. Here the 
practised eye and good judgment are useful to detect and to decide 
whether the variation is a desirable one. If desirable the new fea- 
ture is preserved and increased by graft or cutting. Itis claimed 
that some varieties resulting from bud-variation become so well . 
established that they may be propagated by seed. However, this is 
notcommon. The new characteristics are said also to be strength- 
ened by a proper selection of buds, and by giving the variant part 
more time on the parent plant. 
Flowers on plants reproduced by seeds are often improved by 
crossing with flowers raised from seeds grown ina different locality. 
Crosses between closely related species followed by proper selec- 
tion result in many new and desirable varieties. This hybridiza- 
tion often hastens the flowering period, increases the size of flowers 
and leaves, and sometimes produces varieties that will thrive where 
the parent plant will not. Doubling is also sometimes a result of 
this crossing of species. 
There has been considerable discussion as to the influence of the 
parent plants in these crosses; that is, as to whether the result will 
be the same when the male parent is selected from one species and 
the female from another as when the selections are reversed. Ex- 
periments in this line are offered to prove both sides. The more 
recent claim and experiments are in accord with the statement that 
the relative influence depends rather upon the vigor of the plant 
than upon the sex. Some hybrids are reproduced by seeds, others 
by asexual methods. The fixing of qualities in hybrids is some- 
times accomplished by breeding with one or the other of the parent 
species. This attempt, however, often results in reversion to the 
parent employed. 
Permanent doubling in some cases is thought by Kemer to result 
from the influence of the gall-mite. 
Another means of yariation needs to be noticed. Listen to Dar- 
win in regard to Adam’s Laburnum: “Throughout Europe, in 
different soils and under different climates, branches on this tree 
have repeatedly and suddenly reverted to the two parent species in 
