IX 
WARNING COLORATION AND MIMICRY 
255 
Although the Heliconidse present, on the whole, many 
varieties of coloration and pattern, yet, in proportion to the 
number of distinct species in each district, the types of 
coloration are few and very well marked, and thus it becomes 
easier for a bird or other animal to learn that all belonging to 
such types are Uneatable. This must be a decided advantage to 
the family in question, because, not only do fewer individuals 
of each species need to be sacrificed in order that their enemies 
may learn the lesson of their inedibility, but they are more 
easily recognised at a distance, and thus escape even pursuit. 
There is thus a kind of mimicry between closely allied species 
as well as between species of distinct genera, all tending to the 
same beneficial end. This may be seen in the four or five 
distinct species of the genus Heliconius which all have the same 
peculiar type of coloration—a yellow band across the upper 
wings and radiating red stripes on the lower,—and are all found 
in the same forests of the Lower Amazon; in the numerous 
very similar species of Ithomia with transparent wings, found 
in every locality of the same region ; and in the very numerous 
species of Papilio of the “ .rEneas ” group, all having a similar 
style of marking, the resemblance being especially close in 
the females. The very uniform type of colouring of the 
blue-black Euplaeas and of the fulvous Acrseas is of the 
same character. 1 In all these cases the similarity of the 
allied species is so great, that, when they are on the wing 
at some distance off, it is difficult to distinguish one species 
from another. But this close external resemblance is not 
always a sign of very near affinity; for minute examination 
detects differences in the form and scalloping of the wings, in 
the markings on the body, and in those on the under surface 
of the wings, which do not usually characterise the closest allies. 
It is to be further noted, that the presence of groups of very 
similar species of the same genus, in one locality, is not at all 
a common phenomenon among unprotected groups. Usually 
the species of a genus found in one locality are each well 
marked and belong to somewhat distinct types, while the 
1 This extension of the theory of mimicry was pointed out by Professor 
Meldola in the paper already referred to ; and he has answered the objections 
to Dr. F. Muller’s theory with great force in the Annals and Mag. of Nat. 
Hist., 1882, p. 417. 
