Xll INTRODUCTION. 



tional peculiarities of its mother.* Thus, the male pa- 

 rent of the Downton Strawberry was the Old Black, the 

 female a kind of Scarlet ; in Coe's Golden Drop Plum, 

 the father was the Yellow Magnum Bonum, the mother 

 the Green Gage ; and in the Elton Cherry the White 

 Heart was the male parent, and the Graffion the female. 



The limits within which experiments of this kind 

 must be confined are, however, narrow. It seems that 

 cross fertilisation will not take place at all, or very rarely, 

 between different species, unless these species are nearly 

 related to each other; and that the offspring of the 

 two distinct species is itself sterile, or if it possesses the 

 power of multiplying itself by seed, its progeny returns 

 back to the state of one or other of its parents. Hence 

 it seldom or never has happened that domesticated fruits 

 have had such an origin. We have no varieties raised 

 between the Apple and the Pear, or the Quince and 

 the latter, or the Plum and Cherry, or the Gooseberry 

 and the Currant. On the other hand, new varieties 

 obtained by the intermixture of two pre-existing va- 

 rieties are not less prolific, but, on the contrary, often 

 more so than either of their parents ; witness the 

 numerous sorts of Flemish Pears which have been raised 

 by cross fertilisation from bad bearers, within the last 

 twenty years, and which are the most prolific fruit trees 

 with which gardeners are acquainted ; witness also Mr. 

 Knight's Cherries, raised between the May Duke and 

 the Graffion, and the Coe's Plum already mentioned. 



It is, therefore, to the intermixture of the most 

 valuable existing varieties of fruit that gardeners should 

 trust for the amelioration of their stock. By this oper- 

 ation the pears that are in eating in the spring have been 



* In early crosses between distinct species this Is particularly 

 manifest ; but in those of varieties long domesticated it is less 

 apparent, the distinctions between the parents themselves being 

 less fixed, and less clearly marked. 



