in Hybridisation 367 



The forms with preponderantly violet-coloured flowers had 

 dark brown, black-brown, and quite black seeds. 



The experiment was continued through two more genera- 

 tions under similar unfavourable circumstances, since even 

 among the offspring of fairly fertile plants there came again 

 some which were less fertile or even quite sterile. Other 

 flower- and seed-colours than those cited did not sub- 

 sequently present themselves. The forms which in the 

 first generation [bred from the hybrids] contained one or 

 more of the recessive characters remained, as regards these, 

 constant without exception. Also of those plants which 

 possessed violet flowers and brown or black seed, some did 

 not vary again in these respects in the next generation ; 

 the majority, however, yielded, together with offspring 

 exactly like themselves, some which displayed white flowers 

 and white seed-coats. The red flowering plants remained 

 so slightly fertile that nothing can be said with certainty 

 as regards their further development. 



Despite the many disturbing factors with which the 

 observations had to contend, it is nevertheless seen by this 

 experiment that the development of the hybrids, with 

 regard to those characters which concern the form of the 

 plants, follows the same laws as in Pisum. With regard 

 to the colour characters, it certainly appears difficult to 

 perceive a substantial agreement. Apart from the fact 

 that from the union of a white and a purple-red colouring 

 a whole series of colours results [in 7^], from purple to pale 

 violet and white, the circumstance is a striking one that 

 among thirty-one flowering plants only one received the 

 recessive character of the white colour, while in Pisum this 

 occurs on the average in every fourth plant. 



Even these enigmatical results, however, might probably 

 be explained by the law governing Pisum if we might 

 assume that the colour of the flowers and seeds of Ph. 

 multiflorus is a combination of two or more entirely in- 

 dependent colours, which individually act like any other 

 constant character in the plant. If the flower-colour A 

 were a combination of the individual characters A^ + A^ ... 

 which produce the total impression of a purple colora- 

 tion, then by fertilisation with the differentiating character, 

 white colour, a, there would be produced the hybrid unions 



