66 Mendel's Experiments 



If we endeavour to collate in a brief form the results 

 arrived at, we find that those differentiating characters 

 which admit of easy and certain recognition in the 

 experimental plants, all behave exactly alike in their 

 hybrid associations. The offspring of the hybrids of each 

 pair of differentiating characters are, one-half, hybrid again, 

 while the other half are constant in equal proportions having 

 the characters of the seed and pollen parents respectively. 

 If several differentiating characters are combined by cross- 

 fertilisation in a hybrid, the resulting offspring form the 

 terms of a combination series in which the permutation 

 series for each pair of differentiating characters are united. 



The uniformity of behaviour shown by the whole of the 

 characters submitted to experiment permits, and fully 

 justifies, the acceptance of the principle that a similar 

 relation exists in the other characters which appear less 

 sharply defined in plants, and therefore could not be 

 included in the separate experiments. An experiment 

 with peduncles of different lengths gave on the whole a 

 fairly satisfactory result, although the differentiation and 

 serial arrangement of the forms could not be effected with 

 that certainty which is indispensable for correct experiment. 



THE REPRODUCTIVE CELLS or HYBRIDS. 



^ 



The results of the previously described experiments 

 induced further experiments, the results of which appear 

 fitted to afford some conclusions as regards the composition 

 of the egg and pollen cells of hybrids. An important matter 

 for consideration is afforded in Pisum by the circumstance 

 that among the progeny of the hybrids constant forms 

 appear, and that this occurs, too, in all combinations of the 

 associated characters. So far as experience goes, we find 



