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GENETIC STUDIES ON THE SILKWORM 
1:3:3:1, though the ratios fluctuate to a certain extent. 
10) Similar dimorphism of gametic series was observed by T. H. 
Morgan and his collaborators in the fruit-fly; but in this insect, coupling 
and repulsion were complete in the male, and partial in the female, in contrast 
to what has been observed in the silkworm. 
11) Independent inheritance has been proved between the following 
factors : 
T (3-moulting) and 0 (opaque skin) T and K (knobbed) 
T and L 
T and Z 
T and Q, 
T and P 
T and M 
T and S 
T and Y 
B (malanic) and L 
B and Z 
B and P 
B and S 
B and M 
0 and K 
B and Y 
0 and L 
0 and Z 
0 and Q, 
0 and P 
0 and M 
0 and S 
0 and Y 
K and L 
K and Z 
K and Q, 
K and P 
K and M 
K and S 
K and Y 
L and Z 
L and Q, 
L and P 
L and M 
L and S 
L and Y 
Z and Q, 
Z and P 
Z and M 
Z and S 
Z and Y 
Q, and P 
P and M 
p and S 
P and Y 
12) A wide range of variation is found in the pigment intensity of the 
normal and quail types. Certain variations transmit their characteristics to 
the offspring: such heritable variations are probably due to the existence of 
