LOSS OF EYE-PIGMENT IN GAMMARUS. Soe 
Matings :—(2) with male a of the same brood, (R-+A) : 
(38 young, 35 Red, 3 Albino) ; 
(3) with a Red male of the same brood which 
it ate ; 
(4) with male VI.A.3.h. (B+A); (92 young, 
52 Black, 40 Albino) ; 
(5) with male VI.A.3.e. (Pure Black); (19 
young, all Black) ; 
(6) with male VI.C.2.d. (Pure Black); (21 
young, all Black) ; 
(7) with a Black male from a brood of 
VI.C.2.dxj.; 2 young, Black. 
VI.B.2.w. Female, Albino carrying Red. 
Matings :—(1) with male s of the same brood ; (38 young, 
all Albino) ; 
(2) with male b of the same brood (R-— <A), 
(222 young, 118 Red, 104 Albino). 
VI.B.3.h. Female, Albino. 
Matings :—(1) with an Albino male I.C.2.d. - one brood. 
all Albino; two survived and mated, 
producing 228 young, all Albino. 
VI.B.4.f. Female, Albino. 
Matings :—(1) with an Albino male (from Brood 3 of 
male VIJ.C.2.r.);\ eggs laid: female 
eaten. 
VI.B.4.¢. Female, Albcno carrying Red. 
Matings :—(1) with an Albino male, a, from Brood 2 of 
male VI.C.1.b. : 
(2) with male b of same brood (R-+<A): 
(132 young, 71 Red, 61 Albino), 
Classes in F, Generation. 
According to Hypothesis II, which has proved to be in agreement with 
the facts so far ascertained, there should be in the F » generation, resulting 
from the mating of two blacks both carrying red and albino, the follow- 
ing different kinds in the proportions shown :— 
Blacks. Constitution. Number. 
Pure Black CCBB I 
Black carrying Albino Ce BB 2 
Black carrying Red CCBR 2 
Black carrying Red and Albino Cc Bk 4 
