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The Variation of Animals and Plants

Chapter XI: On Bud-Variation
BUD-VARIATION IN THE PEACH, PLUM, CHERRY, VINE, GOOSEBERRY, CURRANT, AND
BANANA, AS SHOWN BY THE MODIFIED FRUIT — IN FLOWERS: CAMELLIAS, AZALEAS,
CHRYSANTHEMUMS, ROSES, ETC — ON THE RUNNING OF THE COLOUR IN CARNATIONS —
BUD-VARIATIONS IN LEAVES — VARIATIONS BY SUCKERS, TUBERS, AND BULBS — ON
THE BREAKING OF TULIPS — BUD-VARIATIONS GRADUATE INTO CHANGES CONSEQUENT
ON CHANGED CONDITIONS OF LIFE — GRAFT-HYBRIDS — ON THE SEGREGATION OF THE
PARENTAL CHARACTERS IN SEMINAL HYBRIDS BY BUD-VARIATION — ON THE DIRECT
OR IMMEDIATE ACTION OF FOREIGN POLLEN ON THE MOTHER-PLANT — ON THE EFFECTS
IN FEMALE ANIMALS OF A PREVIOUS IMPREGNATION ON THE SUBSEQUENT OFFSPRING —
CONCLUSION AND SUMMARY.
This chapter will be chiefly devoted to a subject in many respects important, namely,
bud-variation. By this term I include all those sudden changes in structure or appearance
which occasionally occur in full-grown plants in their flower-buds or leaf-buds.
Gardeners call such changes "Sports;" but this, as previously remarked, is an ill-defined
expression, as it has often been applied to strongly marked variations in seedling plants.
The difference between seminal and bud reproduction is not so great as it at first appears;
for each bud is in one sense a new and distinct individual; but such individuals are
produced through the formation of various kinds of buds without the aid of any special
apparatus, whilst fertile seeds are produced by the concourse of the two sexual elements.
The modifications which arise through bud-variation can generally be propagated to any
extent by grafting, budding, cuttings, bulbs, etc., and occasionally even by seed. Some
few of our most beautiful and useful productions have arisen by bud-variation.
Bud-variations have as yet been observed only in the vegetable kingdom; but it is
probable that if compound animals, such as corals, etc., had been subjected to a long
course of domestication, they would have varied by buds; for they resemble plants in
many respects. For instance, any new or peculiar character presented by a compound
animal is propagated by budding, as occurs with differently coloured Hydras, and as Mr.
Gosse has shown to be the case with a singular variety of a true coral. Varieties of the
Hydra have also been grafted on other varieties, and have retained their character.
I will in the first place give all the cases of bud variations which I have been able to
collect, and afterwards show their importance These cases prove that those authors who,
like Pallas, attribute all variability to the crossing either of distinct races, or of distinct
individuals belonging to the same race but somewhat different from each other, are in
error; as are those authors who attribute all variability to the mere act of sexual union.
Nor can we account in all cases for the appearance through bud-variation of new
characters by the principle of reversion to long-lost characters. He who wishes to judge
how far the conditions of life directly cause each particular variation ought to reflect well
on the cases immediately to be given. I will commence with bud-variations, as exhibited
in the fruit, and then pass on to flowers, and finally to leaves.
 
 
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