86 Menders Experiments 



two original stocks differ in seven characters, and 100 and 

 200 plants were raised from the seeds of their hybrids to 

 determine the grade of relationship of the offspring, we can 

 easily see how uncertain the decision must become, since 

 for seven differentiating characters the combination series 

 contains 16,384 individuals under 2187 various forms ; 

 now one and then another relationship could assert its 

 predominance, just according as chance presented this or 

 that form to the observer in a majority of cases. 



If, furthermore, there appear among the differentiating 

 characters at the same time dominant characters, which 

 are transferred entire or nearly unchanged to the hybrids, 

 then in the terms of the developmental series that one of 

 the two original stocks which possesses the majority of 

 dominant characters must always be predominant. In the 

 experiment described relative to Pisum, in which three 

 kinds of differentiating characters were concerned, all the 

 dominant characters belonged to the seed parent. Although 

 the terms of the series in their internal composition 

 approach both original stock plants equally, in this experi- 

 ment the type of the seed parent obtained so great a 

 preponderance that out of each sixty-four plants of the 

 first generation fifty-four exactly resembled it, or only 

 differed in one character. It is seen how rash it may be 

 under such circumstances to draw from the external resem- 

 blances of hybrids conclusions as to their internal nature. 



Gartner mentions that in those cases where the develop- 

 ment was regular among the offspring of the hybrids the 

 two original species were not reproduced, but only a few 

 closely approximating individuals. With very extended 

 developmental series it could not in fact be otherwise. 

 For seven differentiating characters, for instance, among 

 more than 16,000 individuals offspring of the hybrids 



