plants. Darwin says ("Animals and Plants under Domestication," vol. i.,
p. 374), "It has often been remarked that we do not owe a single useful
plant to Australia, or the Cape of Good Hope--countries abounding to an
unparalleled degree with endemic species--or to New Zealand, or to
America south of the Plata; and, according to some authors, not to
America north of Mexico." In other words, the domesticated plants are
only found within the limits of what I shall show hereafter was the
Empire of Atlantis and its colonies; for only here was to be found an
ancient, long-continuing civilization, capable of developing from a wild
state those plants which were valuable to man, including all the cereals
on which to-day civilized man depends for subsistence. M. Alphonse de
Candolle tells us that we owe 33 useful plants to Mexico, Peru, and
Chili. According to the same high authority, of 157 valuable cultivated
plants 85 can be traced back to their wild state; as to 40, there is
doubt as to their origin; while 32 are utterly unknown in their
aboriginal condition. ("Geograph. Botan. Raisonnee," 1855, pp. 810-991.)
Certain roses--the imperial lily, the tuberose and the lilac--are said
to have been cultivated from such a vast antiquity that they are not
known in their wild state. (Darwin, "Animals and Plants," vol. i., p.
370.) And these facts are the more remarkable because, as De Candolle
has shown, all the plants historically known to have been first
cultivated in Europe still exist there in the wild state. (Ibid.) The
inference is strong that the great cereals--wheat, oats, barley, rye,
and maize--must have been first domesticated in a vast antiquity, or in
some continent which has since disappeared, carrying the original wild
plants with it.

CEREALS OF THE AGE OF STONE IN EUROPE

Darwin quotes approvingly the opinion of Mr. Bentham ("Hist. Notes Cult.