Even in Europe we have somewhat similar facts, for the species and varieties of butterflies peculiar to the Island of Sardinia are generally smaller and more deeply coloured than those of the mainland, and the same has been recently shown to be the case with the common tortoiseshell butterfly in the Isle of Man; while _Papilio Hospiton_, peculiar to the former island, has lost the tail, which is a prominent feature of the closely allied _P.

Machaon_.
"Facts of a similar nature to those now brought forward would no doubt be found to occur in other groups of insects, were local faunas carefully studied in relation to those of the surrounding countries; and they seem to indicate that climate and other physical causes have, in some cases, a very powerful effect in modifying specific form and colour, and thus directly aid in producing the endless variety of nature." [Illustration: OUTLINES OF WINGS OF BUTTERFLIES OF CELEBES COMPARED WITH THOSE OF ALLIED SPECIES ELSEWHERE.
Outer outline, _Papilio gigon_, of Celebes.

Inner outline, _P.

demolion_, of Singapore and Java .-- 2.

Outer outline, _P.