LOSS OF EYE-PIGMENT IN GAMMARUS. 347 
(c) Those which give normal and no-white eyes in two colours in the 
proportions 3:1:3: 1. 
Normal Black Normal Red 
B+R+NxR+N Black. No-white. Red. No-white. 
Experiment = 45 1 24 10 
Theory 31 10 31 10 
B+R+AxR+N 
Experiment fh 3 3 | 
Theory 6 2 6 2 
(d) Those which give normal and no-white eyes in three colours in the 
proportions 9:3 79:3: 6: 2. 
B+R+A+N Normal Black Normal Red Normal os 
x R+A+N Black. No-white. Red. No-white. Albino, (Albino No- 
white). 
Experiment 109 53 157 45 104 23 
Theory 138 46 138 46 92 30) 
(ec) Those which give normal and no-white eyes in three colours in the 
Proportion: 21 s9):-923---12) = 4, 
B+R+A+Nx Normal Black Normal Red Normal _Colourless 
B-_R sey \ ZeNi Black. No-white. Red. No-white. Albino. ee &. 
Experiment 442 153 155 77 212 58 
Theory 461 154 154 51 205 68 
9. Matings of animals, one normal-eyed carrying no-white, the other 
no-white. 
(a) Those which give normal and no-white eyes in one colour in the 
proportion |: 1, 
Normal Black. Black No-white. 
B+NxBN+R Experiment 20s 12 
Theory 16 16 
Normal Red. Red No-white. 
R+NxRN Experiment 11 15 
Theory 13 13 
(b) Those which give normal and no-white eyes in two colours in the 
‘proportions 3: 3:1: 1. 
Normal Black Normal] Red 
Black. No-white. Red. No-white, 
B+R+NxBN+R Experiment 26 21 3 10 
Theory 22°5 22-5 75 Td 
4 
Section IV. By breeding together “albinos” and “ no-whites” a 
certain proportion of offspring are produced in which both the coloured 
retinal pigment and the white extra-retinal pigment are absent. The 
