Larvae and their Work 



in the ground ; he hatches from an egg laid in the soil by 

 the mother beetle. 



A curious, almost repulsive, creature is the tiger-beetle 

 larva. Nearly at the centre of his body there is a peculiar 

 kink, so that his outline is, roughly, that of the figure 3. 

 His head is massive, horny and flattened, and it serves him 

 well for more than one purpose. In early life he uses his 

 hard, flat head as a hod on which to carry the earth from 

 the spot where he hatched to the surface of the ground, 

 and thus he forms his burrow. This subterranean home 

 may be more than a foot in length, and is perfectly 

 vertical. On the completion of the excavation the 

 creature's head serves another purpose : it acts as a stopper 

 for the burrow. Thus, at the open end of its earthen 

 home, the larva will await its living meal for hours on 

 end. Any insect passing near its formidable jaws is 

 seized and drawn into the burrow, to be devoured at 

 leisure. 



There is one most interesting point in connection with 

 this larva which we have not mentioned. We remarked 

 that its outline is that of a figure 3 ; well, on the 

 hinder end of the creature's back that is, on the outer 

 edge of the lower loop there are a pair of sharp hooks 

 which serve a useful purpose. By their means the larva 

 hooks itself into position at the mouth of its burrow ; 

 when any prey is caught, the hooks are released and the 

 larva, with its victim, drops to the bottom of its lair, like 

 the proverbial streak of lightning. The home of the 

 tiger-beetle larva is indeed a simple structure compared 

 with some of the constructions built by other larvae. 



Some of the caddis-fly larvae, like those of the tiger- 

 beetle, are flesh-eaters ; they also construct lairs, but they 

 live in water and not in the ground. The homes of these 

 water-dwellers are so diverse that we cannot describe 

 them all in detail. Two species cut green leaves into 

 almost rectangular pieces and fasten their edges together, 

 so as to form complete tubular or rectangular mantles, as 



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