A much smaller but very peculiar 

 genus of beetles, is called the Bombardier 

 (Brachinvs,) from its extraordinary power 

 of discharging from its tail end a very pun- 

 gent fluid, accompanied by a report (re- 

 sembling the sound pJnit) and some smoke- 

 like vapour ; this fluid, which resembles 

 nitric acid in its efiects, and makes a stain 



on the fingers that will last for several 

 Fig. 75. for its defence against more powerful 



days, is 



beetles. 



no 



Fig 



doubt intended 

 75 represents 



one of these beetles (B ftnnavs Linn.j ; its head, thorax, and legs are yellowish- 

 red, and its wing-covers dark blue. Like other ground beetles, it may be found 

 under sticks and stones in the spring, and in similar hiding-places on the damp 

 margin of rivers during the hot summer months. There are quite a number of 

 different species of this genus in Canada, but all are very much alike. 



It would be almost an endless task to go through the list of species of this 

 family, but we trust that the examples now given will be sufficient to enable our 

 readers to recognize these friendly beetles, and save them from being doomed to 

 a pitiless destruction, that knows no diiference between friend and foe. 



3. Water Beetles {Dytiscidm, Gyrinidm the.) 



After the carnivorous Ground Beetles, we come, in the ordinary classification of insects 

 to a large group that live almost entirely in or upon the water. Some of them live on the 

 surf loe of lakes, ponds and pools ; others prefer clear running streams ; others, again, the 

 muddy bottoms of half stagnant pools. 



This group is divided into two principal families, the "diving-beetles" (DyUscidce) . and 

 the "whirligigs" {Gijrinida'). They are all more or less insectivorous, both in their larval 

 and perfect state, and hence beneficial. As their food, however, consists mainly of insects 

 that inhabit the water, and which are either similar in their food and habits to their destroy- 

 ers, or live upon water plants of no particular value, it can hardly be said that they are bene- 

 ficial to the farmer or fruit-grower ; still, as they are not noxious and are certainly useful in 

 their own sphere, we shall go on to describe them, and implore that their lives may be spaied 

 from the destruction so universally dealt out to the poor insects. 



The Diving-beetles {Dt/tiKidw) are mostly large-sized insects of an oval flattened shape, 

 generally of a dark brown, olive, or blacki.sh colour, and often with a margin and other mark 

 ings of yellowish. Their legs are specially adapted for swimming, being large and oar-like, 

 and covered with long hairs ; the hinder pair are very much flattened, also, so as to give a 

 propelling stroke. When they rise to the surface to take in a fresh supply of air — a silver- 

 like bubble of which may generally be seen attached to their hinder extremities — they appear 

 to come up merely from being specifically lighter than the water; but when they dive or swim 

 through the liquid, which they do with great swiftness, they move by means of regular and 

 successive strokes of their oar-like legs. When at rest upon the surface they extend these 

 legs at right angles with the body, generally with the head under water and the tip of the 

 abdomen above, enabling them to draw in air to the spiracles beneath the wing-covers. They 

 inhabit stagnant pools in preference to running water, and are very voracious in their habits, 

 attacking and devouring other denizens of the water, even occasionally preying upon very 

 young fish. We have kept a specimen for many weeks in a glass jar of water, and watched 

 its graceful movements and curious habits with much interest; it fed greedily upon house- 

 flies, aphides, etc., with which we supplied it. 



Their larvaj are called "water tigers" from their ferocity ; they are long and cylindri- 

 cal, with large flattened heads, armed with scissors-like jaws, by means of which they 

 seize other insects, and, it is said, "snip off the tails of the tadpoles! "Their body termi- 

 nates in a pair of long tubes through which they inhale the needful supply of air. When 

 about to transform they creep into the earth near by, and make a round cell, inside of 

 which they assume the pupa state, the perfect beetle appearing in two or three weeks, if in 

 summer, but not till the following spring if in the autumn. We have sometimes seen 

 little pools of water in the spring perfectly swarming with these and other larvse. 



