—T, see”.h 
WHITE CATTLE: AN INQUIRY INTO THEIR ORIGIN, ETC. 229 
of Choiseul Sound (which almost divides the island into two 
parts) white beasts with black heads and feet are the most 
common. In all parts, black and some spotted animals may be 
observed . . . It is thus,” he adds, “interesting to find the 
once-domesticated cattle breaking into three colours.” This, of 
course, indicates the prepotency of three separate ancestral types. 
1 As regards the question of colour, a writer in the Quarterly Review for 
1869, says—‘‘ But we know that colour is the most variable of all an animal’s 
characters, and yet in a state of nature colour as a rule is very constant in 
each species. Mr. Darwin has shown, however, that colour is often 
intimately associated with other constitutional peculiarities. In Virginia 
the paint root (Lachnanthes tinctoria) is eaten by pigs, and makes their 
hoofs drop off. But black pigs are uninjured by it. Consequently, in 
places where this plant is abundant the farmers never keep any but black 
pigs, as no others can be raised except in confinement. Here we have a 
beautiful illustration of the mode of action of ‘natural selection.’ The pigs 
of Virginia are not all born black any more than in other countries, but 
those of all other colours soon die, and therefore in a state of nature a 
black race would be produced ; and from the powerful action of the law of 
hereditary descent there can be little doubt that in time the litters would 
consist almost entirely of black pigs. If after this had happened it were 
first discovered that white or brown pigs could not live in the district, we 
should have a.striking example of adaptation; but the adaptation would 
evidently be an adjustment brought about by the simple law of ‘natural 
selection’ or ‘survival of the fittest,’ and the rigid extermination of all 
individuals not adapted to the surrounding conditions. It can be easily 
seen that in this case ‘natural selection’ does not imply a personal selector, 
since exactly the same result must happen whether the farmer kills off the 
white pigs himself and turns the black ones loose, or turns out all together. 
This case, although curious, is by no means isolated. White terriers suffer 
most from distemper, and white chickens from the gapes. In Sicily the 
Hypericum crispum is poisonous to white sheep alone. White horses suffer 
severely from eating honey-dewed vetches, while chestnuts and bays are 
uninjured. Purple plums in North America are subject to a disease from 
which green and yellow plums are free. Again, the white pigeons of a 
flock are the first to fall victims to the kite. White rabbits of a very 
hardy kind have been turned loose but fail to maintain themselves, and 
black fowls on the west coast of Ireland are picked off by sea-eagles. Here 
we have the explanation of the otherwise puzzling fact, that white 
quadrupeds and birds are so rare in nature, although abundant among all 
domesticated animals; and the explanation is all the more satisfactory 
because it accounts for the exception to the rule in the case of many arctic 
birds and quadrupeds as well as of sea birds, for to these the white colour 
is a protection instead of a danger.” 
