BRITISH INSECTS 



and adult forms have been found in a fossil state. Re- 

 mains of an insect allied to the present creatures has 

 also been recorded from carboniferous strata, which 

 actually measured two feet in expanse of wings, so that 

 since that far-off time insects have greatly decreased 

 in size. The oval-shaped eggs are deposited in the 

 water, and in due course the hungry and voracious 

 larva makes its appearance. It is one of the terrors of 

 the pond, or stream, in which it resides, and is dull 

 grey, or brownish-green, in colour. It is the possessor 

 of a curious two-jointed " mask," which can be tucked 

 away, or extended, at will. On the outer joint a pair of 

 strong jaws are situate, and these are capable of great 

 execution upon the body of a victim. Woe betide 

 any unwary creature upon whom the predatory larva 

 decides to prey. Although it crawls sluggishly on the 

 bed of the water, the larva has the power of forcing its 

 way through the liquid element by means of a remarkable 

 contrivance which runs through the centre of its body. 

 The larva is very unlike the adult, and when the nymphal 

 state is reached only the presence of rudimentary wings 

 distinguishes it from the larva. When ready to emerge, 

 the nymph leaves its watery home, climbs up the stem 

 of an adjacent plant, rail, or post by the water-side, 

 and waits for the greatest event of its mysterious life. 

 The skin spHts, and after a series of efforts and gymnas- 

 tic performances, the perfect insect emerges. During 

 these evolutions it turns, at least, one complete somer- 

 sault, and onlv those who have been fortunate enough to 

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