Helianthus Annuus Syncotylcns. 467 
tricotylous strains. Whether from this a pure, almost 
tin variable syncotylous race can be raised, which would 
no longer be an intermediate race, but show to this the 
same relation as that between the aurea varieties and 
variegated plants (see p. 21), is a point on which we 
are at present completely in the dark. 
As already stated, I found my race in the year 1887. 
At that time I had sowed a large quantity of seed of 
Helianthus annuus, obtained in exchange from different 
botanical gardens, and found 18 syncotyls amongst 500 
seedlings. I planted out these only. They flowered to- 
gether, but the seeds of each individual were saved, sown 
o 
and examined separately. In 17 lots the proportions of 
syncotylous seedlings were distributed between 1 and 
15%, and in the case of only one of them it was 19%. 
The latter plant had had its cotyledons fused up to their 
upper margin and was selected as the basis of my race. 
The offspring of the other plants were not grown, and 
moreover from this selected individual only syncotylous 
seedlines were chosen for further cultivation. 
o 
These flowered together and were left to be pollinated 
by insects. This is apparently necessary in this species, 
or at any rate in my race of it, because isolated indi- 
viduals fertilized with their own pollen, either artificially 
or by humble bees, set no seed. In the later generations 
the seed has always been collected separately from each 
plant, and in the following spring sown with a label 
bearing the number of the parent, and examined. In 
this way I obtained hereditary values for each single 
plant. 1 The seeds are large and few plants produce as 
many as 300 seedlings, so that the values are not so 
1 This rule holds without exception, and therefore I shall not 
mention it in the description of the experiments which are to follow. 
