PARNELL, AYYANGAR, RAMIAH, AND AYYANGAR i9l 
was obviously of the constitution Gg Tt, and the two families followed 
up were— 
No. 431 gg Tt givingasimple 3: / ratio of ripening straw : ripening 
gold, Table V. 
No. 432 GgTT giving al: 2:1 ratio of tipped gold: patchy gold: 
ripening straw, Table VI. 
In both cases further generations confirmed these results. 
A large amount of material arising from various crosses has now been 
examined and in all cases the above explanation of the behaviour of 7 is in 
strict accordance with the results. It appears, however, that there may be 
some other factor producing slight modifications. Thus in some groups the 
tipped golds are quite distinct, whereas in others they are not easily separable 
from some of the patchy golds. Similarly in some groups the ripemng 
straws constantly show specks of gold, whereas in others this is very rare. 
Below are given the results from two crosses between pure types, and 
also the summarized results of several generations from certain natural crosses 
in which the same factors are concerned. 
Tipped gold, GGT T, x dark gold, GGtt, gave tipped gold in F,. A 
simple 3: 1 ratio of tipped gold : dark gold resulted in IF’, as follows :— 
Tipped gold Dark gold 
Gee 
G t 
No. 2596 ae 599 184 
Calculated 3: 1 : 587 ° 196 
Dark gold, GGtt x ripening straw, gg T T, gave patchy gold in F,. Six 
groups appeared in F, but patchy and tipped golds were counted together, 
as also dark and medium golds. ‘The figures for the four main groups sepa- 
rated were as tollows :— 
GoLpD RIPENING 
Tipped & patchy | Dark & medium | Straw Gold 
Caan G t oa gt 
No. 2581 .. Ae 1,335 455 443 170 
Calculated 9:3:3: 1 iT apsysl & 451 & 451 f 150 
Similar results were given by a natural cross of which the progeny have 
been followed up in some detail. The F, appeared as a patchy gold plant in a 
family giving a simple 3 : / ratio of ripening straws to ripening golds. This 
cross, No. 748 N, was obviously of the constitution Gg T t, as No. 2581 above, 
since it gave the same groups in F . 
