130 Mr. A. D. Darbishire. On Crossing Round with |June 20, 
p-grains. For, in the first place, no round grains appeared in 80 seeds from. 
16 plants which bore only round seeds. In the second place, of the 
100 round seeds borne by plants bearing both round and wrinkled, 40 had 
p-grains as against the 33 or 34 expected by my theory—a discrepancy not 
so great that it cannot be accounted for by the smallness of the number of - 
‘seeds. © | 
Fic. 6.—Starch grains of DR Round Peas in F;,. 
If the association of 7-grains with heterozygote round, and of p-grains 
with homozygote round holds good for the F, generation, we have a means 
of distinguishing between D D round and D Rf round in Fy»; instead of, as at 
present, having to wait until their progeny are mature in the following year. 
A further point is demonstrated by the nature of the grains in Fj, and 
borne out by those in F;. It is that the shape of the grain is inherited. 
separately from its composition—if we may use this term to cover the 
singleness or compoundness of the grain. In the round pea the grains are 
single and long; in the wrinkled they are compound and round; in the 
hybrid they may be either single or compound, but are more round than long. 
In a subsequent generation, F;, we have v-grains exhibiting much compound- 
ness (54.23) and others exhibiting little (54.182 1, 11, iv, and v). We have 
(possibly) p-grains either with no compounds, or with few ; and intermediate 
grains either with few compounds (54.179 1) or with many (54.179 11). 
The wrinkled peas contained, as was to be expected, c-grains, but some of . 
them contained in addition, very sparingly, p-grains, one of which is shown 
in fig. 7. 
