Recent Advances in the Study of Heredity. 171 
sow the seed I found to my great surprise, that the colour of the Peas 
instead of being a deep blue , like their female parent, was of a 
yellowish white like the male. Towards the end of the summer I 
was equally surprised to find that these white seeds had produced 
some pods with all blue, some with all white, and many with both 
blue and white peas in the same pod. 
Last spring I separated all the blue peas from the white and 
sowed each colour in separate rows, and I now find that the blue 
produce only blue, while the white seeds yield some pods with all 
white and some with both blue and white Peas intermixed. 
The edible qualities of this Pea I have not tried, having but 
few ..” 
Later on he says “ should this new variety of Pea neither 
possess superior merit, nor be deemed singular in its bi-coloured 
produce, yet there is, I conceive, something in its history that will 
emit a ray of physiological light.” Little can Goss have 
imagined how fully that prophecy was destined to be fulfilled eighty 
years later. 
The phenomena as they appeared to Goss may be summarized 
in the following diagram, in which Y signifies yellow and G, green. 
Y X G 
Y Fj generation. 
Y G F 2 generation. 
Y G G F 3 generation. 
Those who are familiar with the details of the Mendelian pheno¬ 
menon will see that this is a correct account of what occurs, except 
that Goss imagined all the yellows in F 2 to produce yellows and 
greens, and that he does not give the relative number of yellows 
and greens in F 2 . 
Let us see what actually occurs. In the first place the ratio 
of yellows to greens in F 2 is as 3 to 1. With regard to the 
other point, let us reflect for a moment what a consideration of the 
ancestry of the F 2 generation might lead us to expect 1 . If we look 
at the ancestry of the F 2 generation we find only one type of green ; 
1 This looks as if we were looking to the ancestry to give an indi¬ 
cation of what will happen in F 2 . This is indeed the case. But 
it is to be noted that the difference between the ancestors to 
which we pay attention are not somatic ones but relate to the 
nature of the offspring (whether uniform or diverse) of the 
several forms. 
