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Darwin, Charles, 1809-1882

"Effects of Cross and Self Fertilisation in the Vegetable Kingdom"

) This is best shown by the impossibility in
many cases of raising two varieties of the same species pure, if they
grow at all near together; but to this subject I shall presently return;
also by the many cases of hybrids which have appeared spontaneously both
in gardens and a state of nature. With respect to the distance from
which pollen is often brought, no one who has had any experience would
expect to obtain pure cabbage-seed, for instance, if a plant of another
variety grew within two or three hundred yards. An accurate observer,
the late Mr. Masters of Canterbury, assured me that he once had his
whole stock of seeds "seriously affected with purple bastards," by some
plants of purple kale which flowered in a cottager's garden at the
distance of half a mile; no other plant of this variety growing any
nearer. (10/13. Mr. W.C. Marshall caught no less than seven specimens of
a moth (Cucullia umbratica) with the pollinia of the butterfly-orchis
(Habenaria chlorantha) sticking to their eyes, and, therefore, in the
proper position for fertilising the flowers of this species, on an
island in Derwentwater, at the distance of half a mile from any place
where this plant grew: 'Nature' 1872 page 393.) But the most striking
case which has been recorded is that by M. Godron, who shows by the
nature of the hybrids produced that Primula grandiflora must have been
crossed with pollen brought by bees from P.


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