DARWINISM 
CHAP. 
cracks and falls to pieces, just as occurs in a wild gourd 
(0. momordica). 1 
Variations of Flowers. 
Turning to flowers, we find that in the same genus as our 
currant and gooseberry, which we have cultivated for their 
fruits, there are some ornamental species, as the Ribes sanguinea, 
and in these the flowers have been selected so as to produce deep 
red, pink, or white varieties. When any particular flower be¬ 
comes fashionable and is grown in large quantities, variations 
are always met with sufficient to produce great varieties of tint 
or marking, as shown by our roses, auriculas, and geraniums. 
When varied leaves are required, it is found that a number of 
plants vary sufficiently in this direction also, and we have 
zonal geraniums, variegated ivies, gold and silver marked 
hollies, and many others. 
Variations of Domestic Animal*. 
Coming now to our domesticated animals, we find still more 
extraordinary cases ; and it appears as if any special quality or 
modification in an animal can be obtained if we only breed it 
in sufficient quantity, watch carefully for the required varia¬ 
tions, and carry on selection with patience and skill for a 
sufficiently long period. Thus, in sheep we have enormously 
increased the wool, and have obtained the power of rapidly 
forming flesh and fat; in cows Ave have increased the produc¬ 
tion of milk; in horses Ave have obtained strength, endurance, 
or speed, and have greatly modified size, form, and colour; in 
poultry Ave have secured various colours of plumage, increase 
of size, and almost perpetual egg-laying. But it is in dogs and 
pigeons that the most marvellous changes have been effected, 
and these require our special attention. 
Our various domestic dogs are believed to have originated 
from several distinct Avild species, because in every part of 
the Avorld the native dogs resemble some wild dogs or wolves 
of the same country. Thus perhaps several species of wolves 
and jackals Avere domesticated in very early times, and from 
breeds derived from these, crossed and improved by selection, 
1 These facts are taken from Darwin’s Domesticated Animals and Cultivated 
Plants, vol. i. pp. 359, 360, 392-401 ; vol. ii. pp. 231, 275, 330. 
