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INSECTS. 
The water-bugs, Hyclrocorisa,are distinguished from the land-bugs, 
water Bugs. on iy by their mode of life, but also by their short inconspicuous 
antennae, and are mostly dull and uniformly coloured insects, frequenting stagnant 
waters, where they swim some on their back, others with the back uppermost. They 
are all comprised in two families. Of these, the water-scorpions (Nepidce) have a 
small narrow head, and their fore-legs are specially modified to serve as prehensile 
organs. Whereas some swim actively, others drag themselves slowly along the 
COMMON BRITISH WATER-BUGS. 
1, The water boatman {Notoneda glauca ); 2, The water-scorpion (Nepa cinerea), with (3) its larva and (4) its eggs ; 
5, JVaucoris cimicoides ; 6. Gorixa geoffroyi ; 7, Ranatra linearis ; 8, Limnobates stagnorum; 9, Pond-skater 
[Gerris paludum), with (10) its eggs and larvae ; 11, Larva of Velia currens (nat. size). 
bottom of the ponds in which they live. They are furnished with an appendage 
looking like a long tail, but consisting of two separate pieces, grooved on their inner 
surface, and capable of being locked closely together to form a tube, which leads 
to the two spiracles placed at the hind-end of the body. When the insects come 
up to breathe, the tip of this breathing-tube may be seen emerging just at the 
surface of the water. The form of the body is in some (Nepa) broad and flat; in 
others (Ranatra) elongated. The female of Nepa lays her eggs in chains on 
aquatic plants, and each egg has seven short processes radiating from one end. 
The eggs of the Ranatra are laid one by one in notches, which the female makes in 
the stems of the plant. 
