I04 NATURAL SCIENCE. August, 



recognises important differences, for " he instructs his budders to cut 

 buds only from the topmost shoots of the nursery rows in order that 

 he may grow straight, vigorous trees ; and every farmer's boy knows 

 that the reddest and earHest apples grow on the uppermost branches, 

 and his father will always tell him that he should never select scions 

 from the centre or lower part of a tree." This practice rests on the 

 principle of acquired characters being hereditary in plants, expressed 

 by M. Carriere, thirty years ago, in the following words^ : — " Faisons 

 aussi remarquer que les diverses combinaisons faites pour perpetuer 

 les varietes, ou pour en obtenir de nouvelles, reposent sur cette loi 

 generale que, dans la nature, tout tend a se reproduire et meme a 

 s'etendre, que par consequent les modifications peuvent non-seulement 

 devenir hereditaires, mais qu'elles peuvent encore servir de moyen 

 pour arriver a d'autres modifications, a etendre et a multiplier de 

 plus en plus les series typiques." 



Bud-variation, however, as ordinarily understood, consists of 

 only the more extreme and readily noticeable forms of variations, as 

 when a nectarine is borne on a peach tree, or laciniate or variegated 

 leaves appear on a tree that ordinarily has entire, or green leaves, 

 respectively, and the like. 



The important point which Mr. Bailey proves is, that bud-varia- 

 tion and seed-variation are not only strictly parallel phenomena, but 

 are really of one kind ; for horticulturists can bring selection to bear 

 on plants raised from bud-variation, or plants propagated by buds, 

 and so " improve " them and fix varieties, just as they do with seed- 

 lings. The author quotes the following passage of Darwin's^ : " To 

 my surprise I hear from Mr. Salter that he brings the great principle 

 of selection to bear on variegated plants propagated by buds, and has 

 thus greatly improved and fixed several varieties. He informs me 

 that at first a branch often produces variegated leaves on one side 

 alone, and that the leaves are marked only with an irregular edging, 

 or with a few lines of white and yellow. To improve and fix such 

 varieties, he finds it necessary to encourage the buds at the bases of 

 the most distinctly marked leaves, and to propagate from them alone. 

 By following with perseverance this plan during three or four 

 successive seasons, a distinct and fixed variety can generally be 

 secured." 



As another parallel between bud- and seed-variation, Mr. Bailey 

 says : " It is well known that the seedlings of plants become more 

 variable as the species is cultivated ; and it is also true that bud-varieties 

 are more frequent and more marked in cultivated plants," many plants 

 having great " sporting" tendencies, as in certain sections of roses, 

 chrysanthemums, etc. The general cause is the same for both kinds 

 of variation, namely, the environment ; or in the words of Darwin : 



1 Production et Fixation des Varietes dans les Vegetaux, p. g. Paris, 1865. 



2 " Animals and Plants under Domestication," i., p. 411. 



