508 Mr. R. Trimen on Mr. Millar s Experimental 
all four, of these possible pairings in nature suggests the 
idea that an important determining influence on the 
discrepant results of rearing from ova to imagines the 
offspring of a ^ of the wahlhergi-^oxm, and (at different 
times, between four and five months apart) the offspring 
of two ^ $ of the mima-iorxn, may perhaps be found in 
similarity or dissimilarity in each case of the two parents; 
that the crossing of the forms may yield a progeny com¬ 
posed of the two different forms in varying proportions; 
while such a result as the thirty-three mima (24 $ ^ and 
9 ^ exclusively from one mother of the mwia-form may 
be traceable to the mating of similar parents. 
At the same time, it should not be forgotten that, in 
the case of PajMio dardanus sub.-sp. eenca, where the $ is 
non-mimetic and, though varying considerably within 
moderate limits, constant to one coloration and pattern, 
the female offspring of two individuals of each form of 
the trimorphic and tri-mimetic $ has been proved, by Mr. 
G. F. Leigh’s breeding experiments in Natal,* to present 
very great discrepancy in the proportional representation 
of the three forms. In the two cases of the predominant 
cenea-form of the ^ progeny reared was respectively 24 
ce7iea and 3 hippocoon in one case, and 15 cenea and 1 
hippocoon in the other; in two cases of the rarer liippocoon- 
form of $ the ^ progeny was re.spectively 8 cenea, 3 
hippocooii, and 3 troplio^ims in one case, and 13 cenea only 
in the other; while, in two cases of the scarce trophonins- 
form, the $ progeny was in one case 2 cenea only, and in 
the other 6 cenea and 1 trophonius. 
With all this discrepancy, however, there stands out—as 
has been well demonstrated by Prof. Poulton {1. c., p. 430) 
—the constant feature of the immense preponderance of 
the cenea-iovm in these six results; and with this may be 
compared the preponderance of the mima-iorm (like the 
cenea-^oxm of the Papilio itself a close mimic of Ainauris 
alhmiacidatd) in the three cases of Euralia wahlhergi-^nmia 
progeny reared by Mr. Millar. 
Since I became aware of the occasional pairing of the 
Natalian Euralia wahlbergi and mima, I have been sur¬ 
prised at not finding in collections any examples more or 
less combining the features of the two forms; indeed, 
* See Prof. Ponlton’s “ Heredity in six families of Papilio Dar¬ 
danus, Brown, sub-species cenea, Stoll, bred at Durban, by Mr. 
(j. F. Leigb, F.E.S.” (Trans. Ent. Soc. Lond., 1908, p. 429). 
