MILLARDET 161 



found in a considerable number of cases that the off- 

 spring resembled one parent only, from which it was 

 indeed indistinguishable, whilst no trace of likeness 

 to the second parent could be detected in it. In some 

 cases the resemblance was to the paternal species 

 (pollen-parent), and in others to the maternal species 

 (seed-parent). In several instances the hybrid off- 

 spring, on being self-fertilized, bred true to the type 

 which they already exhibited, so that the second 

 generation, like the first, seemed to derive its whole 

 constitution from one parent, to the total exclusion 

 of the other. 



The precise meaning of this remarkable phenomenon 

 is not clearly understood. There is some doubt as to 

 whether Millardet's experiments were really sufficient 

 to establish it as a scientific fact. Moreover, Millar- 

 det's observations have never been confirmed by later 

 workers. In the absence of directly contradictory 

 evidence it seemed necessary to draw attention to the 

 facts as they have been described. 



Great numbers of observations upon the character- 

 istics and behaviour of hybrid plants and animals have 

 been from time to time recorded, and the preceding 

 pages contain only a brief selection of such facts as 

 are most necessary for a proper understanding of 

 modern work in hybridization. Until quite recently 

 the laws of transmission of characters in hybrids were 

 still completely hidden. The facts were wonderful 

 enough, but they showed no signs of falling into an 

 orderly arrangement. In the next chapter it will be 

 our business to describe the remarkable discovery 



ii 



