Principles of Heredity 163 



of about the height of "Ringleader" ; but the coloured -flowered 

 sorts varied altogether as to height, period of ripening, and 

 colour and shape of seed*. Those seeds with violet-coloured 

 envelopes produced nearly all maple- or parti-coloured seeds, 

 and only here and there one with a violet-coloured envelope ; 

 that colour, again, appeared only incidentally, and in a like 

 degree in the produce of the maple-coloured seeds t. 



In 1869 the seeds of various selections of the previous year 

 were again sown separately ; and the white-seeded peas again 

 produced only plants with white flowers and round white seeds J. 

 Some of the coloured seeds, which I had expected would produce 

 purple-flowered plants, produced plants with white flowers and 

 round white seeds only ; the majority, however, brought plants 

 with purple flowers and with seeds principally marked with 

 purple or grey, the maple- or brown-streaked being in the 

 minority |j. On some of the purple-flowered plants were again 

 a few pods with peas differing entirely from the remainder on 

 the same plant. In some pods the seeds were all white, in 

 others all black, and in a few, again, all violet IT ; but those plants 

 which bore maple-coloured seeds seemed the most constant and 

 fixed in character of the purple-flowered seedlings**, and the 

 purplish and grey peas, being of intermediate characters, ap- 



being the unit? In any case the possibility makes the experiment 

 well worth repeating, especially as Correns has seen a phenomenon 

 conceivably similar. 



* Being a mixture of heterozygotes (probably involving several 

 pairs of allelomorphs) and homozygotes. 



f This looks as if the violet colour was merely due to irregularity 

 of xenia. 



Pure recessives. 



Pure recessives in coats showing maternal dominant character. 



|| Now recognized as pure homozygotes. 



U This seems almost certainly segregation by flower-units, and is 

 as yet inexplicable on any other hypothesis. Especially paradoxical 

 is the presence of " white " seeds on these plants. The impression is 

 scarcely resistible that some remarkable phenomenon of segregation 

 was really seen here. 



** Being now homozygotes. 



112 



