GENETICS: CASTLE AND HADLEY 
43 
FIGS. 14, PHOTOGRAPHS OF FOUR ENGLISH RABBITS FORMING A GRADED SERIES IN 
AMOUNT OF COLORED FUR. 
These were adopted as our standard Grades 1-4, in terms of which all the rabbits described in these experi- 
ments have been classified. 
FIG. 5, RABBIT cf 21A, FATHER OF THE SERIES I YOUNG. 
FIG. 6, RABBIT cf 40A, FATHER OF THE SERIES II YOUNG. 
