The Isolation of Tricotylous Intermediate Raees. 435 



Let us now summarize the whole culture, which ex- 

 tended over six years. We obtain the following series: 



VALUES IN THE HARVESTS OF 



1892 1893 1894 1895 1896 1897 



Highest value 7 8 25 41 79 79 



Mean " 5 6 13 26 50 64 



Lowest " 2.2 7 15 22 48 



x\s already stated, the intermediate race had therefore, 

 in this case been isolated only gradually from the mix- 

 ture, chieih' as the result of the originally small extent 

 of the cultures. 



Papaver Rlweas. In 1895 I selected 21 tricotylous 

 seedlings from a sowing of the double garden variety 

 of this plant with mixed colors. They yielded an abun- 

 dance of seed, which gave the following percentage of 

 tricotyls, counted in groups of 300 seedlings each : 



18 19 19 20 



12 12 



7 7 8 



4 4 4 4 6 



0.5 1 1 1 1 1 2 



This group plainly exhibits two sections, a half curve 

 with an apex at 1 % and 4 seed-parents with the proportion 

 of 18 to 20%. Obviously these four belong to the inter- 

 mediate race sought for, whilst the rest are partly hybrids 

 between the two races. The best tricotylous seedlings of 

 the two parents with 18 and 19% were planted out in 

 1896. They flowered and set an abundance of seed. 

 The determination of the hereditary values from lots 

 of 300 seedlings each gave a result for one of the two 

 parents, with 24 offspring, of 10 to 56% with a mean 

 of 19%, and for the other from 10 to 53% with a mean 

 of 26%. Seedlings were planted out from the two best 



