594 REPORT—1904. 
the remaining 70 white grains. It appears, therefore, that Mendel’s law (as enun- 
ciated by Correns, namely, that the germ cells represent in equal numbers all 
possible combination of paired characters, no two members of the same pair occur- 
ring in the same germ cell) is truly followed, but that there is considerable irregu- 
larity in dominance. 
The red colour does not appear as an immediate consequence of cross-fertilisa- 
tion, and is, therefore, more difficult to deal with. It appears only in the offspring 
of the cross (white x red), being situated in the pericarp, and, therefore, a plant- 
and not an endosperm-character. 
The evidence shows that if a ‘red-coated’ plant of unknown parentage is 
crossed with white and the ‘red-coated’ offspring again crossed by white, 
50 per cent. of the plants resulting from this cross will show the red character 
and 50 per cent. not. It is therefore highly probable that Mendel’s law is 
followed in this case also. 
Specimens were exhibited showing various regular combinations of the characters 
dealt with. 
7. Experiments on Heredity and Seax-determination im Abraxas grossu- 
lariata. By Rev. G. H. Raynor and L. Doncaster. 
In the currant moth (Abraxas grossulariata) a rave variety oceurs known as 
var, lacticolor or flavofasciata, found hitherto in the female sex alone. The Rev. 
G. H. Raynor has bred this species for several years, and the following is a 
summary of his experiments. 
Var. lacticolor is recessive in the Mendelian sense, not appearing at all in the 
first cross. In the offspring, of heterozygotes paired together half the females 
are lacticolor, the remainder of the females and all the males being normal grossu- 
lariata (1). For example, the numbers bred in one family of this class were 
25 normal ¢ g, 14 normal ¢ 2,9 Jlacticolor 2 Q ; in another, 22 normal ¢ g, 
9 normal 2 3, 9 lacticolor 2 @. 
When, however, a Jacticolor 9 is paired with a first cross g (namely, 
L¢ x G@(L)¢), among the offspring, not only some of the females, but also some 
of the males are Jacticolor (2). The numbers available are not yet enough to 
determine with certainty what are the proportions; in one family there were 
10 normal, 6 dacticolor § gf, 4 normal and 2 lacticolor 9 9. 
The facts may be summarised in genealogical tables thus :— 
(1) sates 
oe 
G(L) ¢ <a 
u's 16@)$ 38 (Seka 1G(L)g¢ +1GG¢g) 
(2) L¢exG¢g 
| 
G(L) 3 ie 
| | Paks wel 
Le @hjg Le aye 
The experiments are of importance in relation to Castle’s hypothesis that 
gametes bear one or the other sex, and that certain somatic characters may be 
coupled with a given sex in the gametes, The hypothesis, if somewhat modified, 
is in excellent accord with the facts; but until we know the result of the pairing 
ene $ xcross-hred 2 it would be premature to draw far-reaching con- 
clusions, 
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