ORDER COLEOPTERA. 



97 



Many male b eetles (especially Lamellicorns and Staphy- 

 linids, Canthon, etc., Fig. 87) are 

 ornamented with horns, which 

 exist only as rudiments or are 

 wholly wanting in the other sex ; 

 in the male Lucanus (Fig. 110) the 

 mandibles are of great size (com- 

 pare also Figs. 88 and 89). Darwin 

 remarks that beetles belonging to 

 many and widely distinct families 

 possess stridulating organs. Cer- 

 tain musical weevils can be heard 

 at a distance of several feet or even 

 yards; the apparatus varying much 

 in position on the body, but usu- 

 ally consisting of a rasp or set of 

 ribs, and a scraper; in many Lon- 

 gicorns the rasp is on the meso- 

 thorax, which is rubbed against the 

 prothorax ; but the apparatus does 

 not differ much according to sex. 

 (Darwin.) 



Protected from harm by their 

 hard shell-like skin and their thick 

 wing - covers, and living, as grubs, 

 as pupae, and as beetles, quite dif- 

 ferent lives, it would be hard to ex- 

 terminate them. Myriad as are 

 their forms, every species has slight- 

 ly different habits and surround- 

 ings from its allies, and thus fills a 

 niche in the insect-world which it 

 alone can occupy. And it is this 

 wonderful power of adaptation to 

 changes in circumstances, as well 

 as their solid skins and complete 

 metamorphosis, which has enabled the great beetle order of 

 over 100,000 kinds to become so abundant and prominent 



i- 



FIG. SQ.CJtiasognathus gran- 

 Hi, reduced. Upper figure 

 male, lower figure female. 

 After Darwin. 



