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XXII. Notes on Seasonal Dimorphism in certain 
African Butterflies. By Arthur G. Butler, 
Ph.D., F.L.S., etc. 
[Read Oct. 16tli, 1895.] 
Mr. Cecil W, Barker's most interesting and instructive 
paper upon this subject is before me, and I only regret 
that the impossibility of risking the effect of night air 
prevented my being present at the meeting in April, 
when it was read, because I note, in the Proceedings of 
the Society, that the question was asked by Prof Meldohi 
whether Mr. Barker's observations had been supported 
by breeding experiments. Although this had not been 
done, our cabinets afford such a mass of evidence in. 
support of his suggestions, that the case may be almost 
considered as good as proved. 
As an example of what is here affirmed I may take 
one example ; that of Teracolns vesta : — 
The form T. argillaceus differs from the typical form 
chiefly in the rosy-ochreous instead of lemon-yellow 
colouring of the undersurface of the hindwings and apical 
area of forewings. If such a difference occurred in one 
type only of the same group, it might fairly be con- 
sidered to have a specific value ; but when we find that it 
recurs throughout the group, whether in Asia or Africa, 
the evidence in favour of its being illustrative of seasonal 
dimorphism becomes almost conclusive ; so much so, that 
most Lepidopterists will certainly accept it, as having the 
authority of proof. 
The following forms of this group of Teracolus in the 
Museum series will, in this event, have to be united : — 
Asiatic Species. 
Summer form Winter form 
1. Unnamed. Teracolus protr actus, Batl. 
2. Teracolus vestalis, Butl. Teracolus intermissus, Butl. 
3. Teracolus puellaris, Butl. Teracolus ochreipennis, Butl. 
TRANS. ENT. SOC. LOND. 1895. — PART IV. (dEC.) 
