MOTIONS OF INSECTS. 413 
yures are diverging rays, which issue either from a basal area or from the 
base itself, and terminate in the exterior margin. The wings of many 
male butterflies, hawk-moths, and moths, are distinguished by a remarkable 
apparatus, noticed by De Geer, and since by many other naturalists ?, for 
keeping them steady and underanged in their flight. The upper wings, on 
their under side near their base, haye a minute process, bent into a hook 
{hamus), and covered with hairs and scales. In this hook one or more 
bristles (tendo), attached to the base of the under wing, have their play. 
When the fly unfolds its wings, the hook does not quit its hold of the 
bristle, which moves to and fro init as they expand or close. The females, 
which seldom fly far, often have the bristles, but never the hook. The 
hairy tails of some insects (Sesic) belonging to the hawk-moth tribe are 
expanded when they fly, so as to form a kind of rudder, which enables 
them to steer their course with more certainty. 
The insects of this and every other order, except the Coleoptera, fly 
with their bodies in a horizontal position, or nearly so. As their wings 
are usually so ample, we need not wonder that the Lepidoptera are ex- 
cellent fliers. Indeed they seem to flit untired from flower to flower, and 
from field to field ; impelled at one while by hunger, and at another by 
jove or maternal solicitude. The distance to which some males will fly is 
astonishing. That of one of the silk-worm moths (Altacus Paphia) is 
stated to travel sometimes more than a hundred miles in this way.” Our 
most beautiful butterfly, the purple emperor (Apatura Iris), when he makes 
his first appearance, fixes his throne on the summit of some lofty oak, from 
whence in sunny days, unattended by his empress, who does not fly, he takes 
his excursions. Launching into the air from one of the highest twigs, he 
mounts often to so great a height as to become invisible. ‘When the sun 
is at the meridian his loftiest flights take place ; and about four in the 
afternoon he resumes his station of repose. The large bodies of hawk- 
moths (Sphinw F.) are carried by wings remarkably strong both as to 
nervures and texture, and their flight is proportionably rapid and direct. 
That of butterflies is by dipping and rising alternately, so as to form a 
zigzag line with vertical angles, which the animal often describes with a 
skipping motion, so that each zigzag consists of smaller ones. This doubt- 
less renders it more difficult for the birds to take them as they fly; and 
thus the male, when paired, often flits away with the female. 
Amongst the neuropterous tribes the most conspicuous insects are the 
dragon-flies (Libellulina), which—their metamorphosis, habits, mode of 
life, and characters considered—form a distinct natural order of them- 
selves. Their four wings, which are nearly equal in size, are a complete 
and beautiful piece of net-work, resembling the finest lace, the meshes of 
which are usually filled by a pure, transparent, glassy membrane. In two 
1 De Geer, i. 178. t. x. £4. Linn, Trans. i. 185, 
2 Linn. Trans. vii. 40. 
5 Haworth, Lepidopt. Brit. i. 19. Mr. Hewitson, in an interesting notice of this 
species, informs us that at Kissengen in Bayaria, where he had an opportunity of ob- 
serving its habits in June and July, 1839, after long and rapid flights in the out- 
skirts of a neighbouring forest, they would enter its most shady recesses to cool 
themselves, and lap the moisture from any puddles of water (preferring the most 
filthy) with their long trunks; and were so eager in this occupation that he has had 
seven under a small flat net at once, and could even take them readily with his finger 
and thumb, (Zntomologist, June, 1842, p. 324.) 
