GAMET fC COUPLING AND KEPULSION IN THE SILKWORM. 
l§7l 
VII. Historical Review. 
Since the phenomenon of gametic coupling was first adequately studied in 
the Sweet Pea by Bateson and his collaborators in 1906, a number of similar 
cases have been observed by these and many other authors. The experimental 
results hitherto known in this field are summarized in the following pages. 
A List of the Known Cases of Gametic Coupling 
and Repulsion. 
I. Gametic Coupling. 
A. Plants. 
Plant name 
Characters 
System 
Authors 
Year 
Sweet Pea 
A)° Blue factor 25 and B) long pollen. 
a) Bed colour and b ) round pollen. 
7 : 1 : 1 : 7 
Bateson, 
Saunders, and 
Punnett. 
1906 
Sweet Pea 
A) Blue factor and B) long pollen. 
a) Bed colour and b) round pollen. 
15 : 1 : 1 : 15 s > 
Bateson, 
Saunders, and 
Punnett. 
1908 
Sweet Pea 
A) Dark axil and B) fertility. 
a) Light axil and b) sterility. 
15 : 1 : 1 : 15 
Bateson, 
Saunders, and 
Punnett. 
1908 
Pea (Pisum) 
A) Tendril and B) round seed. 
a) No-tendril or ‘ acacia ’ type and b) 
wrinlded seed. 
63 : 1 ; 1 : 63 
de Vilmorin 
and Bateson. 
1911 
- 1 .. I„ 
1) A and B express the dominant characters, while a and b denote the corresponding 
recessive factors. 
2) When the blue factor exists the flower is purple. 
3) The 7 : 1 series was observed in the Fi families of the cross Blanche Burpee X 
Emily Henderson, while in F3 of the same cross the gametic system followed was of 15 : 
1 : 1 : 15 type. The latter was also the case with the Fj offspring of Bush X Cupid crosses. 
