COMMON COCKCHAFER. 81 



different kinds, and also from a great number of these 

 injuring the crop, both in the grub, and in the Beetle 

 state, this order is, perhaps, the most important of all 

 to the farmer. 



It will be noticed that, so far as we have advanced, 

 there is just, so to say, a step onwards in the number 

 of legs and wings in each order. Flies have usually 

 one pair of wings, and their maggots are usually leg- 

 less. Fleas have also legless maggots, but in the 

 perfect insect the position of two pairs of wings is 

 marked by scales. In the Beetles we find that the 

 maggots or grubs are sometimes legless, but also 

 sometimes have three pairs of jointed legs, — one pair 

 on each of the three segments nearest the head, and 

 also a sucker-foot beneath the tail, which serves to 

 help in moving, or to hold fast with when pulled at. 



Beetles, as a rule, have two pairs of wings (see Fig. 

 74, p. 89). The upper pair, or wing-cases, which are 

 known as the elytra, are hard and horny, and form a 

 cover or " sheath " for the lower pair ; and from this 

 the order of Beetles takes its name of Coleoptera, or 

 sheath-winged. The under wings are membranous 

 and large when spread out in flight ; when at rest 

 they are folded both lengihicise and across, so as to fit 

 under the wing-cases. Sometimes the under wings 

 are absent, which is a very important consideration 

 in preventive measures. The jaws are horizontal, 

 somewhat like toothed pincers laid flat, so as to work 

 against each other from side to side. 



The Beetle chrysalis is much like the perfect Beetle 

 in shape, but without power of moving about. It lies 

 with the forming limbs, and mouth parts, beneath it, 

 usually all cased in separate sheaths, like a thin outer 

 skin, until it is matured, when it gradually frees its 

 limbs, and gains its full colour and powers.* 



Though there are such great numbers of different 

 kinds of Beetles, the distinctions between the chief 



* For figures of Beetles in their larval, pupal and complete coiuli- 

 lions, see the illustrations in this and the following Chapter. 



G 



