THE LEPIDOPTERA. 
73 
merits of cabbages, carrots, or oak leaves as their future nourish- 
ment, for, at the most, she dips her long sucker into a few 
flowers to enjoy their sweetness. Nevertheless she deposits her 
e ggs in a safe place, and as near as possible to the ordinary 
nourishment of the future caterpillar. 
It is impossible to explain the varieties of the colouring of 
some groups of the Lepidoptera , or the remarkable resemblances 
which exist between the tints of others. Sometimes all the 
species of a genus have the same shades of colour and markings. 
The most brilliantly tinted kinds belong to the hottest and 
moistest climates ; for instance, South America, the Moluccas, 
and certain parts of India. 
Several groups of species belonging to the great genus Papilio 
have a very uniform system of decoration. Species of this genus, 
which are found in the Moluccas, in the neighbourhood of the 
Straits of Sunda, in India, and in Southern China, have black 
velvety wings, dusted with a metallic blue or green tint, and 
ornamented with spots or bands of the same shade. Other 
species of the genus belonging to South America, to the Antilles, 
and to Mexico, are distinguished on account of a flaring red 
spot, or a band with opalescent tints, which ornament the black 
hinder wings. Multitudes of others have their wings variegated 
with yellow and black colours. 
The Pieridi, whose type is the great Cabbage Butterfly, have 
usually white wings, and the species of the genus Colias have 
them tinted yellow ; moreover, most of those of the genus 
Morphos , of South America, have their wings brilliantly coloured 
with a metallic blue. 
Thus there is a sort of uniformity in the ornamentation and 
colouring of more or less widely spread natural groups of the 
Lepidoptera. But if we seek the reason why, and endeavour 
to discover the end that Nature had in view in giving certain 
shades of colour to certain species, we shall not obtain very 
satisfactory answers. It is known that the brilliant colouring 
depends upon the presence of the scales, so far as the Lepidoptera 
are concerned, and the microscope has proved that no inherent 
and tangible colouring matters exist in those tiny dust-like 
particles. The delicate ridges and net-work of the scales act 
