Chap. XI. 



ACTION OF THE MALE ELEMENT. 



397 



to complete or partial reversion, we have seen that undoubted 

 seminal hybrids and mongrels are similarly liable. On the whole, 

 I am inclined to put trust in M. Adam's statement ; and if it 

 should ever be proved true, the same view would probably have 

 to be extended to the Bizzarria and Trifacial oranges and to the 

 apples above described. Although it is at present impossible to 

 arrive at any certain conclusion with respect to the origin of these 

 remarkable trees, the various facts above given appear to me to 

 deserve attention under several points of view, more especially 

 as showing that the power of reversion is inherent in Buds. 



On the direct or immediate action of the Male Element on the 

 Mother Form. — Another remarkable class of facts must be here 

 considered, because they have been supposed to account for 

 some cases of bud-variation : I refer to the direct action of the 

 male element, not in the ordinary way on the ovules, but on 

 certain parts of the female plant, or in the case of animals on 

 the subsequent progeny of the female by a second male. I may 

 premise that with plants the ovarium and the coats of the 

 ovules are obviously parts of the female, and it could not have 

 been anticipated that they would be affected by the pollen of a 

 foreign variety or species, although the development of the 

 embryo, within the embryonic sack, within the ovule, within the 

 ovarium, of course depends on the male element. 



Even as long ago as 1729 it was observed m that white and blue varie- 

 ties of the Pea, when planted near each other, mutually crossed, no doubt 

 through the agency of bees, and in the autumn blue and white peas 

 were found within the same pods. Wiegmann made an exactly similar 

 observation in the present century. The same result has followed several 

 times when a variety with peas of one colour has been artificially crossed 

 by a differently-coloured variety. 117 • These statements led Gartner, who was 

 highly sceptical on the subject, carefully to try a long series of experiments : 

 he selected the most constant varieties, and the result conclusively showed 

 that the colour of the skin of the pea is modified when pollen of a 

 differently-coloured variety is used. This conclusion has since been con- 

 firmed by experiments made by the Eev. J. M. Berkeley. 118 



Mr. Laxton of Stamford, whilst making experiments on peas for the ex- 

 press purpose of ascertaining the influence of foreign pollen on the mother- 

 plant, has recently 119 observed an important additional fact. He fertilised 



11 ' ' Philosophical Transact./ vol. xliii., 

 1744-45, p. 525. 



117 Mr. Swayne, in « Transact. Hort. 

 Boc.,' vol. v. p. 234 ; and Gartner, ' Bas- 



tarderzeugung,' 1849, s. 81 and 499. 



118 ' Gard. Chron.,' 1854, p. 404. 



119 Ibid., 1866, p. 900. 



