EHOPALOCEEA. 
33 
notice alike of eager foes or wary prey are sufficiently obvious ; and 
this is very materially aided by any strong resemblance to inorganic 
substances, to plants, to inoffensive animals in tbe case of prey, and to 
offensive ones in the case of enemies. Every one is familiar with cases 
of colour-likeness to general surroundings, such as those of desert ani- 
mals to the desert sands, arctic animals to the white expanse of snow, 
arboreal animals to the green of foliage. Numerous more special resem- 
blances to inanimate or vegetable objects are also matter of common 
observation, but those of one animal to another of different structure 
are comparatively rare, and are little known except to naturalists, 
although they are perhaps the most remarkable of all. 
Butterflies and Moths are quite exceptionally defenceless ; there is 
not a single instance in the whole Order of a species possessing either 
offensive weapons or defensive armour ; nor does any one of them prey 
on other animals. While, therefore, they have no need of disguise to 
enable them to steal unobserved upon a watchful prey, they require 
more than any other equally large group of insects protection from 
enemies by concealment/ and it is not surprising to find all the three 
kinds of protective resemblances above mentioned strikingly developed 
among them. Without here considering the very numerous cases 
among Moths, it will be interesting to notice some of the more promi- 
nent instances in Butterflies. 
It is the immense size of their wings that renders butterflies so 
conspicuous ; their bodies are small even in the largest species, but the 
wings cover a considerable area, the smallest known Lyccena measuring 
half an inch in expanse. When to this broad field bright and strongly 
contrasted colours are, as often happens, added, the eye is at once 
arrested by so large and distinct an object. Although, when settled, 
the erect position of the wings in nearly all butterflies reduces the 
visible area by one-half, and although, when thoroughly at rest, this 
is still further lessened by the mode in which the fore-wings sink 
between the hind-wings, yet the exposed surface is of considerable 
size.^ On the wing, the great swiftness of some species, and the 
exceedingly uncertain wavering motions of others, enable them to 
evade their enemies ; but when at rest, it is obvious that their main 
refuge must be sought in concealment. It is found, accordingly, that 
the under side is protectively marked and coloured, being rendered 
inconspicuous by either its dulness or its resemblance to the immedi- 
ately surrounding objects. As instances of this among South- African 
species, I may mention the universal Pyrameis Carditi, the beautiful 
Junonia Cebrene and J. Clelia^ and several kinds of Zeritis, all of 
^ The known enemies of butterflies are birds, lizards, dragon-flies, hawk-flies {Asilidce, 
&c.), MantidcB, and spiders. The birds and dragon-flies seize them chiefly on the wing, the 
others pounce on them when settling or at rest. 
^ A good many Erycinidce and Besperidce have the singular habit of settling on the 
under side of leaves with wings fully expanded, so that their own under side is not at all 
exposed, and the whole insect hidden from view from above. 
VOL. I. C 
