♂ 103, an evenly marked rat of grade +3. A female rat of this same
grade was mated with ♂ 8000 (the wild gray male). Two litters of _F_₂
grandchildren are shown in 8062-8067, and 8070-8074.
8062 is black hooded, +2; 8064 is gray hooded, +2; 8065 is black, +5;
8066 is gray, +5¼; 8067 is gray, +4½ (notice white feet).
8070 is black hooded, +2; 8071 is gray hooded, +1¾; 8072 is gray, +5;
8073 is black, +5½; 8074 is gray, +5¾.
[Illustration: PLATE 3]