246 
DARWINISM 
CHAP. 
Other Examples of Mimicry among Lepidoptera. 
In tropical Asia, and eastward to the Pacific Islands, the 
Danaidee take the place of the Heliconidse of America, in their 
abundance, their conspicuousness, their slow flight, and their 
being the subjects of mimicry. They exist under three 
principal forms or genera. The genus Eupltea is the most 
abundant both in species and individuals, and consists of fine 
broad-winged butterflies of a glossy or metallic blue-black 
colour, adorned with pure white, or rich blue, or dusky mark¬ 
ings situated round the margins of the wings. Danais has 
generally more lengthened wings, of a semitransparent greenish 
or a rich brown colour, with radial or marginal pale spots; 
while the fine Hestias are of enormous size, of a papery or 
semitransparent white colour, with dusky or black spots and 
markings. Each of these groups is mimicked by various 
species of the genus Papilio, usually with such accuracy that 
it is impossible to distinguish them on the wing. 1 Several 
species of Diadema, a genus of butterflies allied to our 
Vanessas, also mimic species of Danais, but in this case the 
females only are affected, a subject which will be discussed in 
another chapter. 
Another protected group in the Eastern tropics is that of 
the beautiful day-flying moths forming the family Agaristidae. 
These are usually adorned with the most brilliant colours ox- 
conspicuous markings, they fly slowly in forests among the 
butterflies and other diurnal insects, and their great abundance 
sufficiently indicates their possession of some distastefulness 
which saves them from attack. Under these conditions we 
may expect to find other moths which are not so pi-otected 
imitating them, and this is the case. One of the common and 
wide-ranging species (Opthalmis lincea), found in the islands 
from Amboyna to New Ireland, is mimicked in a wonderful 
manner by one of the Liparidse (the family to which our 
common “ tussock ” and “ vapourer ” moths belong). This is 
a new species collected at Amboyna during the voyage of the 
Challenger, and has been named Artaxa simulans. Both 
i See Trans. Linn. Soc.,x ol. xxv. Wallace, on Variation of Malayan 
Papilionidae ; and, Wallace’s Contributions to Natural Selection, chaps, iii. and 
iv., where full details are given. 
