336 ft, J. ALLEN AND E. W. SEXTON, 
INDEPENDENT ORIGIN OF CoLouRED No-wHitTE AND ALBino No-WHITE 
oR COLOURLESS EyEs, 
In the last section colourless-eyed animals were described amongst 
the grandchildren of the cross Albino eye by No-white eye, and it was 
shown that these were to be expected according to theory. These 
animals always had the eye colourless on both sides of the head. 
Instances of colourless eyes have also occurred in two families amongst 
the offspring of our original Albino female mated with a pure Red male 
(Cross A) (Plate I). 
(1) The Red-eyed male (I.F.) mated with the Red female (I.E.) had 
a very large number of young, 780 in twenty-six broods, 589 red 
eyes and 191 albinos (Plate I). Amongst the reds there was a small 
number of individuals in which the white extra-retinal pigment had 
become reduced or entirely disappeared, giving rise to the typical Red 
No-white eye. In 24 animals the white had almost but not entirely 
disappeared from one or both eyes, only a few small specks of white 
being discovered with a l-inch power, four on right side, eight on left 
side, and twelve on both sides. In 14 animals the eye on one side had 
no white pigment (12 on the right side, 2 on the left), that on the other 
was normal. In 5 animals the white pigment had completely disappeared 
from both eyes, the eyes being typical Red No-whites. 
A similar state of things occurred amongst the Albinos. In seven 
animals the white pigment had entirely disappeared from the eye of one 
side (5 on the left side and 2 on the right side), and was present as usual 
in the eye of the other side. In one animal the white pigment was absent 
from both eyes, which therefore were quite colourless (see pp. 286 
and 339.2). 
The following are the details of the No-whites in the successive broods :— 
In Brood 1, one Red-eyed animal had the right eye affected, there being 
only a fleck or two of white ; when mature the eye was completely no-white. 
It died without offspring. Another had very thin reticulation in both eyes. 
(Several of the next generation had hardly any white pigment in their eyes.) 
In Brood 2, one Red-eyed animal had the right eye completely no-white. 
In Brood 3, one Albino-eyed animal had the right eye small, and the left 
eye no-white, i.e. Colourless. (From the mating of two albinos of this 
Brood 3, 12 young were produced, one of which was Colourless on the right 
side, and one was Colourless on both sides. In the next generation again, 
10 young were obtained from the mating of two of the normal albinos, and 
one of these again showed the no-white strain, having the right eye Colour- 
less.) 
In Brood 4, the animals were all normal-eyed. One Albino, a female, was 
mated with the Red male from Brood 1, which had very thin white reticula- 
