28 
which my expei'iments can throw any important lif,4it. I have for a 
long while had the idea that the red was the primitive form, hnt this 
was based on ntterly inadecpiate grounds—chiefly, 1 believe on the 
ground that this is the only colour in the allied siiadicrctria ; and I 
fancied it obtained some slight measure of support from the results of 
my breeding, where the proportion of red to black females is on the 
whole much higher than that of red to black males—red to black 
females roughly as 8 : 9, red to black males hardly more than Gi ; 9, 
(I am working on the assuinjijtion that the female is the more conser¬ 
vative sex, as is so strongly maintained by many evolutionists). On 
closer reflection, however, I think there is at least as much, if not more, 
to he said for the other view, namely, that the black is the original 
form. It crops up in nearly every brood, in a way somewhat suggestive 
of ata^ism, audit seems impossible to eliminate, while the red element 
can he eliniinated in a generation or two, by selection of black parents. 
()f course it may be suggested in reply that the black form is in some way 
peculiarly advantageous, and is constantly struggling to assert itself ; 
hut if .so, it is difficult to see why atavism never (apparently) occurs, 
and if it does not, how it is that the original red form is not extinct 
by this time. .\nd as ivgai'ds the answering of my arguments (such 
as they were) for the greatei- antiipiity of the red form, it will suffice to 
remark that the red hand-coloration is on the whole rare in this family, 
that the allied sjiailirrarid is apparently a more recent species,- and 
may have branched off after the evolution of the red form of fcrnitiata ; 
and that the relatively high pro])ortion of red /Iaudas in breeding has 
chiefly been brought about by a fewof the/utrr bi'oods, where successive 
red pairings had been selected in the parentage, and where, conse- 
(piently, one might almost regal'd them as the more plastic rather than 
as atavistic. 
Asregards my second question, “ What purpose does the dimorphism 
subser\e, or how was it brought about ? ” 1 have not even a theory 
to offer. 1’he exact value of the “ Carpet ” patterns and coloration 
of my favourite Ceometrids, in relation to natural selection, is by no 
means so clear to me as I suppose it ought to he. Packard has in¬ 
stanced the ah. imidnitaria as a case of melanism, and seems to hint 
that he regai'ded it as a result of climatic conditions ; hence, I suppose, 
he \\evfed f(‘n ii</ata, Linn., as the older form. Mr. Sydney W^ehh, on 
the other hand, once spoke of the red form as furnishing“ “ the only 
instance of mimicry known to me among the Lritish Lepidoptera.'” 
This is not an impossible explanation, if the black is the original form, 
hut there is at present absolutely no evidence for it. And it would he 
an insuperable obstacle in the way of my suggestion that sjiadircdrid 
(which is of course assumed to be the species mimicked) has recently 
sprung from the red form of jCrvdiidtd. Only carefully directed 
experiments, such as those of Poulton and others with other species 
{I’roc. Xddl. Six-., March, 1887, Ac.), can elucidate this question. 
I now turn to the statistics of my “ heredity experiments,” and 
such thoughts as are called forth by them. 1 have alreadv said that I 
have bred altogether ,72 separate broods, hut that I am working this 
evening on data dei'ived from 88 only. The remaining 19 are accounted 
* Vi'lc, Traiiit. CiUj of Ixmd. Kid. ,(■ X. }[. Sor., ]H!H, p. ;31, where 1 have 
referred to the restricted geographical range of ('. upadiccorid. 
