I1EMIPTERA. 



97 



Fig. 74. Hydrometra stagnorum. 



have linear bodies. The head, which forms nearly the third of the 

 entire length, is furnished with two long antennae, and armed with a 

 thin, hair-like beak. The legs are long, and of equal length. The 

 reader may have often seen the Hydrometra stagnorum walking by jerks 

 on the surface of the water (Fig. 74). The body and legs tare of a fer- 

 ruginous colour, the hem elytra 

 a dull brown, and the wings 

 hyaline, or glassy, and slightly 

 blackish. Geoffrey says that it 

 resembles a long needle, and 

 calls it the Needle Bug. 



The Hydrocorisa, or Water 

 Bugs, have the antennae shorter 

 than the head, or scarcely at- 

 taining to its length, and inserted and hidden under the eyes, which 

 are in general of remarkable size. All these Hemiptera are aquatic 

 and carnivorous. We will mention the two principal types, the Nepce, 

 or Water Scorpions, and the Notonecta, or Boatmen. 



The Nepa cinerea (Fig. 75), which Geoffroy calls the Oval-bodied 

 Water Scorpion, and which he also designates by 

 the name of the Water Spider, is very common in 

 the stagnant waters of ponds and ditches. Its body, 

 oval, very flat, of an ashy colour, with red on the 

 abdomen, is four-fifths of an inch long. The 

 hemelytra are horizontal, coriaceous, and of a dirty 

 grey colour. Its front legs, with short haunches, 

 and very broad thighs, are terminated by strong 

 pincers, which give to the insect a strong resem- 

 blance to the scorpion. It is by folding back the 

 leg and the tarsus under the thigh, that the animal 

 holds its prey, and sucks it with its rostrum or beak. 



This rostrum is composed of three joints, and 

 contains four pointed bristles. Two present on one 

 side a sort of narrow sharp blade, and have teeth 

 towards their base. Of the two others, the one* 

 is a thin smooth needle, the other is provided with Fig. 75--Ne P a cinerea. 

 hairs directed backwards and forwards. 



It is with this rostrum, which resembles a case of surgical instru- 

 ments, that the Nepa pierces and sucks little aquatic insects, not even 

 sparing its own species. Its wound is painful to man, but not in the 

 least dangerous. With its four hind legs the Nepa swims, but at a 

 very slow pace. It generally drags itself along the bottom of the 



