PIERIS. 
Ill 
Not fewer than one hundred and sixty-six diffe- 
rent kinds of butterflies are referred to this genus. 
“ They are diffused," says Dr. Boisduval, “ nearly 
over the whole globe, but are particularly abundant 
in the intertropical countries of the old continent. 
Considering the extent of the New World, it pro- 
duces comparatively few species. The most re- 
markable inhabit Africa, the Indian continent and 
Archipelago, and New Holland. Such of the ca- 
terpillars as are known, feed almost exclusively on 
the crucifera ). , rcsidacece, tropiolue, and caparidece. 
Our P. Cratcegi is the only one in Europe which 
lives on trees ; but it is probable that many exotic 
kinds are of the same habits. The prevailing colour 
among these lepidoptera is white, more or less pure, 
with a black border, variable in width, but seldom 
wanting. There are likewise species in which the 
ground colour is yellow or even orange, while in 
others it is blackish or blue, &c. The inferior face 
of the posterior wings generally differs considerably 
from the upper, and is often very agreeably varied 
with brilliant colours. The sexual differences, in 
certain species, are very conspicuous, particularly on 
the surface; in others, they are much less so, the 
females being distinguished from the males only by 
a somewhat wider border, or by having the upper 
wings more rounded at the apex*.” 
Species genunil dea I.epidopterea, i. p. 435. 
