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cal agriculture the brothers Carton two Lancashire farmers, 

 achieved great practical success by crossing different varieties 

 of food yielding plants, and sometimes these with weeds 

 belonging to the same species. The crossing was effected 

 in two stages. First, crosses likely to give the best results 

 were effected, and in the next generation plants showing the 

 desired effect were crossed with each other to fix the type. 

 The principle of a second crossing can be carried on still 

 further to fix the type permanently and avoid reversions to 

 the original types. 



703. There is a natural disinclination on the part of plants 

 to hybridise. If the natural pollen and the pollen of another 

 species are placed upon a stigma, the foreign pollen remains 

 inert, and even when the natural pollen is applied a little time 

 subsequent to the foreign pollen, it acquires the supremacy 

 and the embryos prove true and never hybrids. Gardeners 

 are not agreed as to the kind of influence exerted by the male 

 and female parents respectively in determining the character 

 of the mule. All that can be said is, the result from the hy- 

 brid seed is a plant differing from both parents, but bearing 

 more or less relation to one or the other and more vigorous 

 than either. Dioecious plants are less prone to hybridise than 

 those with hermaphrodite flowers. The seeds resulting from 

 hybridisation are in the majority of cases barren. In many 

 cases only a portion of the seeds formed produce fertile 

 plants ; while in some cases the hybrid plants are just as 

 fertile as their parents. It is observed that in fertile hybrid 

 plants, the flowers earliest opened are the most fertile, or 

 sometimes they are the only ones that ripen seed, subse- 

 quent flowers often developing fruits the seeds of which are 

 destitute of an embryo. Atavism, or returning to the original 

 type of one of the parents, is a frequent chracteristic of the 

 hybrid. In some hybrids the progeny forming the second 

 and third generations become more fertile than the original 

 hybrid. The resulting progeny from cross-breeding is in- 



