STATES OF INSECTS. (Larva.) 185 
longitudinal rays or bands, at others in transverse ones. 
Sometimes they are waved or spotted, regularly or irre- 
gularly ; at others they are sprinkled in dots, or minute 
streaks, in every possible way. Various larve are of the 
colour of the plant on which they feed, whence they are 
with difficulty discovered by their enemies. ‘Thus, a large 
proportion of Lepidoptera are green of different shades, 
sometimes beautifully contrasted with black bands; a cir- 
cumstance which renders the caterpillars of two of our 
finest insects of this order as lovely as the fly: I mean 
that of Papilio Machaon and Saturnia Spini. Very fre- 
quently the larvee of quite different species resemble each 
other so exactly, in colour as well as shape, as scarcely 
to be distinguishable: this sometimes takes place even 
where they belong to different genera, as in those of En- 
dromis versicolor a moth, and Smerinthus Populi a hawk- 
moth. And it sometimes happens, very fortunately for 
distinguishing allied species, that where the perfect in- 
sects very nearly resemble each other, the larve are 
altogether dissimilar. ‘Thus, the female of Pontia Rape 
is so much like the same sex of P. Brassica, that it might 
be taken for a variety of it, did not the green caterpillar 
of the one, and the spotted one of the other, evince the 
complete distinction of these butterflies. Cucullia Lac- 
tuca, umbratica, and several other species of the same 
tribe, which includes C. Absinthii, Verbasci, Chamomille, 
Abrotani, are so extremel y alike, that the most practised 
eye can scarcely discover a shade of difference between 
them, though their larvee in colour and markings are 
constantly distinct?. ‘The markings of species belong- 
ing to the same family are usually different ; but in some 
* Wien. Verz. 219. 
