■WATEB-BUGS, WATEE-SCOEPIONS, ETC. 235 



escaped from its aquarium, and on. replacing it in its proper 

 quarters it struggled seemingly so unsuccessfully to sink that 

 I assisted it with the gentle pressure of a finger. The upper 

 part of the insect's abdomen beneath the wings is bright red, 

 and the rest of the body is a darkish brown. The Ranatra 

 will sometimes breed in confinement, but the larvse are difficult 

 to rear. They will not hesitate, if they lack a sufficiency of 

 suitable food, to feed upon one another, the younger ones falling 

 victims to the older. It is necessary for success to provide them 

 with a considerable variety and quantity of small aquatic animal 

 life. The eggs are longer than those of Nepa cinerea, and are 

 fuiTiished with only two filaments or bristles each instead of 

 seven. These filaments are passed, pressed together, through 

 the leaf of some water-plant, such as that of the Frog-bit 

 (Hydrocharis morsus-ranoB), and immediately after insertion they 

 open, and thus the egg is fixed securely to the leaf. Sometimes 

 as many as half-a-dozen eggs will be found hanging to the same 

 leaf. The eggs, according to the temperature of the water, 

 hatch in about a month. The young Ranatrce from the first 

 are in shape very like their parents, but lighter in colour. 

 B. linearis will live a long time in captivity if properly cared 

 for. It should be fed on the same kind of food as that recom- 

 mended for its relative the Nepa. The two Water-scorpions 

 must not be kept together in the same aquarium. R. linearis, 

 which is rarer than the Nepa, can generally be bought for 

 about a shiUing, during the summer, of London dealers in 

 aquarium articles. 



The Naucoris cimicoides (Fig. 148) 

 is rather a rare insect. It is about 

 4in. in length, oval in shape, and of an 

 olive-brown colour. It is not provided 

 with respiratory filaments like those of 

 the Nepa and the Ranatra. It is able Fig. IW. Naucokis 



f.i«. Ji_-Jl i •' CIMICOIDES. 



owing to its fringed hind-legs, to swim 

 very much faster than the two " water- 

 scorpions" previously mentioned. A little care is necessary 

 in handling this insect because of its power to inflict a 

 rather painful wound. Its habits and habitat are similar to 



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