. 

 INSECTS BUGS 187 



small portion near the tip transparent ; the hind-wings are membranous, 

 and are folded beneath the others except when in flight. There are more 

 than 10,000 species ; but fortunately few, comparatively speaking, are 

 British. They possess a long sucking proboscis, curved down beneath 

 their bodies. Most suck the juices of plants, but some prey on smaller 

 insects and a few on animals. Shield-bugs, of which we possess but few 

 species, are identified by the shield or plate which covers the whole of 

 the wings. Pentagonal Shield-bugs have five-sided shields. These may be 

 found among bushes ; they are brown or green in colour and about half an 

 inch long. The most notorious of all is the Bed-bug (Cimex or Acanthia 

 lectularia), a wingless insect, with a very flat body and almost circular abdomen. 

 During the day it lurks in crevices and cracks, to emerge at night in search 

 of its victim, from which (and all too frequently from whom) it sucks the blood 

 until it is enormously distended. The female lays fifty eggs four times a year, 

 between March and September, the larvae being like the parents. The first 

 three broods reach maturity in about eleven weeks, the last brood appears 

 to perish, while the adults survive through the winter. This insect appears 

 to have come from the East, and was known both to Greeks and Romans. 

 It emits an offensive smell (like the Pentagonal Shield-bugs). Other species 

 infest pigeons and swallows. 



There are many other species known as Field-bugs and Water-bugs, the 

 latter being entirely aquatic. One of the former, Acanthosoma griseum, a British 

 species, found in birch trees, shows remarkable maternal care, the female 

 conducting her thirty or forty young as a hen with her chickens, showing 

 great uneasiness when they seem threatened with danger, and waiting by 

 them instead of trying to make her own escape. 



There are three familiar "Water-bugs," to which a brief allusion must 

 suffice. 



The Water-boatman (Notonecta glauca). The third pair of legs are remark- 

 ably long and fringed with hairs, and are used as oars ; the insect rows itself 

 along on its back, and when resting with these rowing legs thrown out " looks 

 like a waterman resting on his sculls." The insect is about half an inch long, 

 and usually a brownish green in colour. It can fly well, but prefers to keep 

 in the water. It can remain under water for some time, taking down a 

 supply of air entangled in the hairs that fringe certain ridges on the abdomen, 

 which thus serve as air chambers. The food consists of animal substances, 

 and it attacks and devours small larvae, fish spawn, etc. 



Corixa is a similar Water-bug, but swims the right way up. It has a curious 

 habit of rubbing its fore-legs across its forehead, probably producing a call-note ; 

 for it is an ascertained fact that these insects can do so, and, conversely, can 

 hear. 



The Water Scorpion (Nepa cinerea) is to be found in many shallow ponds 

 and pools, where it will be almost buried in the mud, with its remarkable 

 seizing legs extended. These are the first pair, which have been modified 



