HEREDITY IN PLANTS, ANIMALS, AND MAN. 367 
‘1. BLACK carryiInc RED < BLACK carRYING RED. 
Blacks. Red. 
Experiment : 3,020 1,066 
Theory . : 3,294 1,098 
5) : 1 
2. BLACK carryYING RED X RED. 
Blacks. Reds. 
Experiment eo 2,079 
Theory : : 2,128 2,128 
i : I 
3. BLACK cARRYING RED AND ALBINO * BLACK caRRYING ALBINO. 
Blacks. Reds. 
Experiment 144 59 
Theory ; A 153 ol 
3) li 
4. BLACK cArRRYING RED AND ALBINO < RED CARRYING ALBINO. 
Blacks. Reds. Albinos. 
Experiment : 235 169 144 
Theory ~-: 205 205 137 
3 : 3 : 2 
5. BLACK carryiNG RED AND ALBINO x BLACK CARRYING RED AND 
ALBINO. 
Blacks. Reds. Albinos. 
Experiment 542 189 241 
Theory ; : 547 182 243 
8) : > : 4 
6. RED CARRYING ALBINO < RED CARRYING ALBINO. 
Reds. Albinos. 
Experiment 1,408 47] 
Theory : 1,409 470 
5) : ] 
DIAGRAM 6. 
EKye-colour of Gammarus, Results of various crosses. 
Hybrid blacks were mated with red-eyed recessive animals. (Diagram 
6.2.) 4,255 young were obtained and examined as soon as extruded from 
the brood-pouch. 2,176 were black-eyed, and 2,079 were red-eyed, which 
is very close to the equality which Mendel’s theory demands. There is 
again a slight deficiency of red-eyes, namely 49. 
This cross of the hybrid with the recessive, which we have already 
studied in the yellow and green peas, is a specially important one to any- 
