PREFACE. 



ix 



sequently their gardens contained few things which would now be deemed worthy 

 of cultivation. The power of obtaining cross-bred varieties at pleasure has only 

 existed since the discovery of sexes in plants ; but as it exerts a most extensive 

 influence over alterations in the vegetable kingdom, it may be considered the 

 most important controlling power that we possess. 



" In sowing seeds for the purpose of procuring improved varieties, care should 

 be had, not only that the seeds be taken from the finest existing kinds; but also 

 that the most handsome, the largest and the most perfectly ripened specimens 

 should be those that supply the seed. A seedling plant will always partake 

 more or less of the character of its parent, the qualities of which are concentrated 

 in the embryo when it has arrived at full maturity. How this concentration, 

 takes place, we are as ignorant as why certain constitutional peculiarities are in 

 men transferred from father to son, and from generation to generation ; but we 

 know that it does take place. Now if the general quaUties of a given variety are con- 

 centrated in the embryo under any circumstances, it is reasonable to suppose that 

 they will be most especially concentrated in a seed taken from that part of a tree 

 in which its peculiar good qualities reside in the highest degree. For, instance, 

 in the fruit of an apple growing upon a north wall there is a smaller formation 

 of sugar than in the same variety growing on a south wall ; and it can be easily 

 understood that the seed of that fruit which is itself least capable of forming 

 saccharine secretions, will acquire from its parent a less power of the same nature 

 than if it had been formed within a fruit in which the saccharine principle was 

 abundant. It should therefore be always an object with a gardener, in selecting 

 a variety to become the parent of a new sort, to stimulate that variety by every 

 means in his power, to produce the largest and the most fully ripened fruit that 

 it is capable of bearing. The importance of doing this is well known in regard 

 to Melons and Cucumbers, and also in preserving fugitive varieties of flowers ; 

 but it is not generally practised in raising fruit trees, 



" The power of procuring intermediate varieties by the intermixture of the 

 pollen and stigma of two uifferent parents is, however, that which most deserves 

 consideration. We all know that hybrid plants are constantly produced in every 

 garden, and that improvements of the most remarkable kind are yearly occurring 

 in consequence. Experiments are, however, it may be supposed, sometimes made 

 without the operator being exactly aware either of the precise nature of the action 

 to which he is trusting for success, or of the limits within which his experiments 

 should be confined. 



" Cross fertilization is effected, as every one knows, by the action of the pollen 

 of one plant upon the stigma of another. The nature of this action is highly 

 curious. Pollen consist of extremely minute hollow balls or bodies ; their cavity 

 is filled vnth fluid, in which swim particles of a figure varying from spherical to 

 oblong, and having an apparently spontaneous motion. The stigma is composed 

 of very lax tissue, the intercellular passages of which have a greater diameter 

 than the moving particles of the pollen. 



" When a grain of pollen comes into contact with the stigma, it bursts and 

 discharges its contents among the lax tissue upon which it has fallen. The mov- 

 ing particles descend through the tissue of the style, until one, or sometimes more, 

 of them finds its way, by routes specially destined by nature for this service, into 

 a little opening in the integuments of the ovulumor young seed. Once deposited 

 there, the particle swells, increases gradually in size, separates into radicle and 

 cotyledons, and finally becomes the embryo, — that part which is to give birth, 

 when the seed is sown, to a new individual. 



" Such being the mode in which the pollen influences the stigma and subse- 

 quently the seed, a practical consequence of great importance necessarily follows, 

 viz. that in all cases of cross fertilization, the new variety will take chiefly after 

 its polleniferous or male parent ; and that at the same time it will acquire some 

 of the constitutional pecuUarities of its mother.* Thus, the male parent 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 GraflSon the female. 



* 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 them- 

 selves being less fixed, and less clearly marked. 



b 



