NET-WINGED INSECTS. 261 
is said of the Cockroaches? What of the Earwigs? What of the 
Praying Mantis? What of the Walking-stick? Of the Leaf In- 
sect? What does the family Saltatoria include? What is said of 
the Mole Cricket? Of the Tree Cricket? How do the Grasshoppers 
differ from the Crickets? What is said of the Katydid? In what 
way is its sound produced? How do the Locusts differ from the 
Grasshoppers? In what countries are they at times exceedingly nu- 
merous? Describe their appearance in Russia in 1825, and the means 
taken to destroy them. What is said of their ravages? Give the de- 
scription from the Prophet Joel of the invasion of an army of Locusts. 
What is said of these insects as food ? 
CHAPTER XXvVI. 
NET- WINGED INSECTS. 
449. Tue insects of the order Neuroptera, or Net-wing- 
ed Insects, have, like the Coleoptera and Orthoptera, a 
mouth fitted for mastication, but differ from them in their 
wings. They have no wing-covers, but there are com- 
monly four thin and transparent wings, with the veins 
forming a delicate net-work, as seen in Fig. 207 (p. 262). 
The posterior wings are ordinarily as large as the ante- 
rior, but in some species they are quite small, and in some 
few entirely absent. The body is long, slender, and soft. 
These insects are of intermediate size, none being either 
very large or very small. There are about a thousand 
species. The metamorphosis is not alike in all. In some 
it is complete, the larva having a form very different from 
the imago or perfect insect, while in others there is little 
difference except in the absence of wings in the larva 
and their presence in the imago, as in the Grasshoppers 
and Locusts. By these differences the order is naturally 
divided into two groups, in the first of which the insect 
is active during its pupa state, while in the other it is 
torpid during this state, except just before its last meta- 
morphosis. Of the first group there are five families, the 
Dragon-flies, Day-flies, Stone-flies, White Ants, and Book- 
