260 INTRODUCTION TO ZOOLOGY chap. 



in the early evening and early morning, flying with a heavy, 

 clumsy flight. They feed on the leaves of many common 

 forest trees, and although their life as winged insects only 

 lasts for six weeks, they may, if they are numerous, do very 

 great damage to the trees, for they sometimes occur in such 

 ruimbers as to be a veritable plague. 



At the end of May or beginning of June, the 

 female chafer lays small yellowish eggs in two or 

 three little clusters of ten or fifteen at a time, each cluster 

 being hidden away in a hole which she excavates in the earth 

 two or three inches down. In five or six weeks the larva 

 hatches, and for over three years it lives underground, feeding 

 at first on decaying organic matter in the soil, but later 

 attacking the roots of plants with its strong jaws, and thus 

 doing much damage. 



The grijihs are soft white creatures with dark horny heads 

 and no eyes. They have six weak black legs, but all power 

 of movement in these is soon practically lost. They hibernate 

 in the soil, lying coiled round as in Fig. 194. The duration of 

 the larval stage varies slightly in different countries, but in 

 England it is usually during the third summer of its life 

 that the larva burrows a little deeper in the ground and 

 pupates for a short while. The perfect insect then throws 

 off its pupal skin, but it still remains underground until 

 the following April or May, so that the beetle is nearly 

 three years old when it first emerges into the air and light, 

 and with a humming noise flies to the trees. 



The Stag Beetles (Liicanus cervus), the largest of 

 ' all British beetles, are also lamellicorn. They 

 have dark-brown bodies, and fly chiefly in the evening. The 

 male may be over two inches long, and he is very formid- 

 able-looking because of the enormous enlargement of the 

 antler-like mandibles (Fig. 195, m), but these apparently 

 are only used in fighting contests to gain a mate, and 

 the beetle feeds most harmlessly on the sweet juice 

 which exudes from oak trees. The larva is much like 

 that of the Cockchafer, but lives for about four years in 

 the decaying wood of the trunks of trees. When full 

 grown, the larva leaves the tree and burrows in the 

 ground, pupating there for a short while. As in the case 

 of the Chafer, the perfect insect which emerges may be 



