NEUROPTERA. 419 
the grace of their movements, have won for them among the 
French their common appellation of “‘ Demoiselles.” They are 
always of largish size. Many are of bright and metallic colours, 
which are not inferior in beauty to those of butterflies. Their 
wings, of an extreme delicacy, always glossy and brilliant, present 
varied tints ; sometimes they are completely transparent, and have 
all the colours of the rainbow. Often, the colour of the males 
differs from that of the females. They may be seen fluttering 
about on the water during the whole summer, especially when the 
sun is at its highest. They fly with extreme rapidity, skimming 
over the water at intervals, and escaping easily when one wishes 
to catch them. Nothing is prettier than a troop of dragon-flies 
taking their sport on the side of a pond or on the banks of a 
river, on a fine summer’s day, when a burning sun causes their 
wings to shine with most vivid colours. 
In the perfect state, as well as in that of the larva and the pupa, 
the Libellulas are carnivorous. Their rapid flight makes them 
expert hunters, and their enormous eyes embrace the whole 
horizon. They seize, while on the wing, flies and butterflies, and 
tear them to pieces immediately with their strong mandibles. 
Sometimes, the ardour of the chase leading them on far from the 
' streams, they are met with in the fields. The female lays her 
egos in the water, from which emerge larve which remind one 
somewhat of the form of the insect, only their body is more com- 
pact and their head flattened. The larvee and pupz inhabit the 
bottom of ponds and streams, where, keeping out of sight in the 
mud, they seek for insects, molluscs, small fish, &e. If any prey 
passes within their reach, they dart forwards, like a spring, a 
very singular arm, which represents the under lip. It is a sort of 
animated mask, armed with strong jagged pincers and supported 
by strong joints, the which, taken together, is equal to the length 
of the body itself. This mask acts at the same time as a lip and 
an arm; it seizes the prey on its passage and conveys it to the 
mouth. ‘‘ When any aquatic insect approaches them at a time 
when they are in a humour for eating,” says Charles de Geer, 
“they shoot the mask forward very suddenly and like a flash of 
lightning, and seize the insect between their two pincers; then, 
drawing back the mask, they bring the prey up to their mandibles, 
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