Chap. XXVII. OF PANGENESIS. 365 



of two plants belonging to distinct species or varieties have become 

 intimately united, buds are occasionally produced which, like 

 hybrids, combine the characters of the two united forms. It is 

 also certain that when trees with variegated leaves are grafted or 

 budded on a common stock, the latter sometimes produces buds 

 bearing variegated leaves ; but this may perhaps be looked at as 

 a case of inoculated disease. The possibility of the production 

 of hybridised buds by the union of two distinct vegetative tissues 

 is an important fact, as it shows us that sexual and asexual 

 reproduction are essentially the same ; for the power of combin- 

 ing in the offspring the characters of both parents is the most 

 striking of all the functions of sexual generation. 



Direct Action of the Male Element on the Female.— In the 

 chapter just referred to, I have given abundant proofs that 

 foreign pollen occasionally affects the mother-plant in a direct 

 manner. Thus, when Gallesio fertilised an orange-flower with 

 pollen from the lemon, the fruit bore stripes of perfectly charac- 

 terised lemon-peel : with peas, several observers have seen the 

 colour of the seed-coats and even of the pod directly affected by 

 the pollen of a distinct variety ; so it has been with the fruit of 

 the apple, which consists of the modified calyx and upper part 

 of the flower-stalk. These parts in ordinary cases are wholly 

 formed by the mother-plant. We here see the male element 

 affecting and hybridising not that part which it is properly 

 adapted to affect, namely the ovule, but the partially-developed 

 tissues of a distinct individual. We are thus brought half-way 

 towards a graft-hybrid, in which the cellular tissue of one form 

 instead of its pollen, is believed to hybridise the tissues of a 

 distinct form. I formerly assigned reasons for rejecting the 

 belief that the mother-plant is affected through the intervention 

 of the hybridised embryo ; but even if this view were admitted, 

 the case would become one of graft-hybridism, for the fertilised 

 embryo and the mother-plant must be looked at as distinct 

 individuals. 



With animals which do not hreed until nearly mature, and 

 of winch all the parte are then fully developed, it is hardly 

 possAle tha the male element should directly affect the 

 female. But we have the analogous and perfectly well-ascer- 

 tamed case of the male element of a distinct form, as with the 



