PHYLUM ARTHKOPODA 



361 



SUBORDER 2. CLAVICORNIA. (CLUB-HORNED BEETLES, 

 Fig. 298.) - - The club-horned beetles have clubbed antennae. 

 They have little in common ; some are 

 aquatic, others terrestrial ; some are pre- 

 daceous, and therefore beneficial; others 

 herbivorous, and consequently harmful; and 

 a few feed on decaying organic matter. 

 Some of the commoner species are known 

 as water-scavenger beetles (HYDROPHILID.<E), 

 rove-beetles (STAPHYLINIDAE), grain beetles 

 (Cucujio^), burying-beetles (SILPHHXE, Fig. FIG 2g8 ._ Order 

 298), and larder-beetles (DERMESTID.E). COLEOPTERA. Car- 



SUBORDER 3. SERRICORNIA. (SAW-HORNED """-.beetle, snpha 



amcncana. (From 



BEETLES, Fig. 299.) --The saw-horned beetles Davenport, after 

 have saw-like antennae. They comprise the ^* 1 ^ a ) rd Natural 

 metallic wood borers (BUPRESTID,E) which 

 injure fruit, shade, and forest trees; the click-beetles (ELATERID.E, 

 Fig. 299), so called because when laid on their backs they are 

 able to spring up with a click ; the death-watch beetles (PTINID^;) , 



some of which make a ticking 

 sound against the wood in which 

 they burrow; the fireflies and 

 soldier-beetles (LAMPYRID.E) , the 

 former nocturnal and occasion- 



<S**ST ( SL C DSS al| y luminous > the latter diur - 



nal and predaceous ; and the 



checkered beetles (CLERID.E), some of which devour the larvae 

 of wood-boring insects. 



SUBORDER 4. LAMELLICORNIA. (BLADE-HORNED BEETLES, 

 Fig. 300.) The blade-horned beetles have antennae whose 

 terminal segments form flat teeth or lamellae. The stag- 

 beetles (LUCANID^E) have received their name because of the 

 peculiar antler-like processes of the males of certain species. 

 The leaf chafers and scavenger-beetles (SCARAB^EID^E) have 

 very different habits, although they belong to one family. The 



