312 
LOCK : STUDIES IN PLANT BREEDING 
sixteen terms may also be shown by the following arrange¬ 
ment :— 
4 A 
8 Aa 
4 a 
> combined with < 
1 B+2 Bb+ 1 b. 
2 B+4 Bb + 2 b. 
1 B + 2 Bb + lb. 
or 
AB + 2ABb + Ab. 
2AaB + 4AaBb + 2Aab. 
aB + 2aBb + ab. 
We see that each pair of allelomorphs behaves indepen¬ 
dently of the other and follows the same rule as that for 
monohybrids.* 
Example III.a. —Sutton’s Telephone Pea, cotyledons 
usually much wrinkled and showing various tints of green 
which tend to become partly or wholly yellow in weathered 
pods,t was crossed with pollen from Ringleader, a smooth- 
yellow-seeded variety. Twelve pods were obtained contain¬ 
ing 42 seeds all completely yellow and smooth or very slightly 
dimpled in form. From these seeds were obtained 33 
plants, which fruited, giving rise to 428 seeds, of which— 
224 were yellow and smooth or slightly dimpled ; 
87 were green and smooth or slightly dimpled ; 
81 were yellow and irregularly wrinkled ; 
26 were green and irregularly wrinkled ; 
or in the proportion 9 : 3 5 : 3*25 : 1*04. 
From the reciprocal cross—Ringleader x Telephone—only 
4 smooth yellow seeds were obtained in two pods. Three 
plants arising from these yielded in F 3 smooth yellow 22, 
smooth green 8, wrinkled yellow 6, wrinkled green 0. 
Example III,b. —Sutton’s Telephone was crossed by pollen 
from the ordinary native Pea grown in Ceylon, having 
smooth nearly spherical seeds and bright yellow cotyledons. 
Eleven of the pods resulting from the cross contained only 
yellow, nearly smooth seeds, 25 in number ; but one such 
* No account of gametes is taken in the above description, which deals 
simply with zygotes (plants). 
f As far as my experience goes some tinge of green can always be 
detected in seeds gathered immediately they are ripe. 
