±32 



ON THE DIRECT ACTION OF THE 



Chap. XL 



dently of the character of either parent, are sometimes developed 

 to a monstrous size ; and the increased size of the pods in the fore- 

 going cases may be an analogous fact. On the other hand, M. de 

 Saporta informs me that an isolated female plant of Pistacia vera is 

 very apt to be fertilised by the pollen of neighbouring plants of 

 P. terebinthus, and in this case the fruits are only half their proper 

 size, which he attributes to the influence of the pollen of P. 

 terebinthus. 



No case of the direct action of the pollen of one variety on another 

 is better authenticated or more remarkable than that of the common 

 apple. The fruit here consists of the lower part of the calyx and of 

 the upper part of the flower-peduncle 144 in a metamorphosed con- 

 dition, so that the effect of the foreign pollen has extended even be- 

 yond the limits of the ovarium. Cases of apples thus affected were 

 recorded by Bradley in the early part of the last century ; and other 

 cases are given in old volumes of the ' Philosophical Transactions ;' 145 

 in one of these a Russeting apple and an adjoining kind mutually 

 affected each other's fruit ; and in another case a smooth apple 

 affected a rough-coated kind. Another instance has been given 146 

 of two very different apple-trees growing close to each other, which 

 bore fruit resembling each other, but only on the adjoining branches. 

 It is, however, almost superfluous to adduce these or other cases, 

 after that of the St. Valery apple, the flowers which, from the ab- 

 ortion of the stamens, do not produce pollen, but are fertilised by 

 the girls of the neighbourhood with pollen of many kinds ; and they 

 bear fruit, " differing from one another in size, flavour, and colour, 

 but resembling in character the hermaphrodite kinds by which they 

 have been fertilised." 147 



I have now shown, on the authority of several excellent 

 observers, in the case of plants belonging to widely different 

 orders, that the pollen of one species or variety, when applied 

 to the female of a distinct form, occasionally causes the coats 

 of the seeds, the ovarium or fruit, including even the calyx 

 and upper j)art of the peduncle of the apple, and the axis 

 of the ear in maize, to be modified. Sometimes the whole 

 ovarium or all the seeds are thus affected ; sometimes only a 



144 See on this head the high 

 authority of Prof. Decaisne, in a paper 

 translated in ' Journ. H >rt. Soc.,' vol. 

 i., new series, 1866, p. 48. 



145 Vol. xliii., 1744-45, p. 525; 

 vol. xlv., 1747-48. p. 602. 



146 ' Transact. Hort. Soc.,' vol. v. 

 pp. 65 and 68. See, also, Prof. 

 Ilildebrand, with a coloured figure, 

 in'Bot. Zeitung,' May 15, 1868, p. 



327. Puvisalso has collected, ' De la 

 Degeneration,' 1837, p. 36) several 

 other instances ; but it is not in all 

 cases possible to distinguish between 

 the direct action of foreign pollen and 

 bud-variations. 



147 T. de Clermont-Tonnerre, in 

 ' Mem. de la Soc. Linn, de Paris,' torn. 

 iii., 1825. p. 164. 



