12 
V. lANAKA, 
Striped )'elIo\v males (No. 8'i3) in one of the families under con- 
sideration were crossed with bixoltine Kasiiri white females, and the off- 
spring; were reared during the summer c^f the same year. The results 
follow : 
Striped 
Strijjcd 
Normal 
Normal 
Total 
yellow 
white 
yellow 
white 
s.6'13 
{Kasuri white ^ x 
162 
84 
74 
178 
4J8 
8'i3 ^) 
S. 7'i3 (ditto) 
222 
188 
410 
S. I 2' I 3 (ditto) 
231 
221 
453 
The matter which 
became c 
ear to us 
from these 
results is 
nothing 
but that some of the striped yellow parents were SsYy, in which 2 : i : 
I : 2 coupling occurred, and so:ne others were SsYY in their zygotic 
constitutions. This gives us, as far as it goes, apparently no clue to 
solution of the question how such a peculiar system as 2 AB : i aB : i ab 
(where A stands for S, B for Y) has been brought forth in the preceding 
generation. Thorough analysis of the case may be expected only after 
sufficient data have been accumulated. 
If we assume a spontaneous elimination (jf S-factor in SsYy $ the 
foregoing case may easily be accounted for. Ikit this assumption is 
evidently prematin^e at present. 
b) A Peculiar Tj'pe of Gametic Coupling between S and Y. 
As mentioned in the foregoing pages the zygotic series in striped- 
yellow coupling are, in usual case, as follows: 
Str. yel. Str. wh. Nor. yel. Nor. wh. 
II : I : I : 3 
or 8:1:1:2 
These are effected from the male gametic series 3:1:1:3 and 2:1: 
I : 2 respectively, the female gametes being i SY : i sy in both cases. An 
aberrant phenomenon from this general rule, however, was observed in the 
families H. 31-2, 3,4^12 in which only two zygotic forms, double domi- 
nant and double recessive, occurred in equal numbers. 
The actual figures and the origin of the families are given below. 
