92 NATURAL HISTORY OF INSECETS. 



CLASS I. Beetles with five-jointed feet (Pentamera). (See 

 Fig. 103.) 



CLASS II. Beetles with five joints in the anterior, and 

 middle feet, and only four joints in the posterior feet (Hetero- 

 mera). (See Fig. 119.) 



CLASS III. Beetles with four joints in each foot (Tetra- 

 mera); such as the Broad-necked Prionus-beetle (Fig. 237), and 

 the Twelve-spotted Diabrotica (Fig. 238). 



CLASS IV. Beetles with only three-jointed feet (Trimera) ; 

 such as the Trim Lady-bird (Fig. 239). 



CLASS I. PENTAMERA. 



A few small insects, although having apparently a less num- 

 ber of joints in their feet than five, are placed in this Class ; 

 in these the first joint is aborted, or rudimentary ; these 

 species are included in the Sub-classes II. and III., defined 

 below. 



The insects belonging to this Class may be divided into six 

 Sub-classes as follows : 



SUB-CLASS I. (Filicornes). Antennae thread-like (filiform), 

 sometimes tapering to the tip (Fig. 94); habits predaceous. 



SUB-CLASS II. (Clavicornes). Antennae becoming thicker 

 towards the tip (clavate, Fig. 92j. These insects mostly feed 

 upon decaying vegetable or animal matter. 



SUB-CLASS III. (Monilicornes.) Antenna) bead-like (monil- 

 iform); wing cases very short. These insects usually feed 

 upon decayed animal matter. 



SUB-CLASS IV. (Pecticornes.) Antenna? pectinate or comb- 

 toothed (Fig. 102); they feed on decayed wood. 



SUB-CLASS V. (Lamellicornes.) Antenna) lamellate (Figs. 

 100 and 101). These insects feed upon excrements or on 

 plants. 



SUB-CLASS VI. (Serricornes.) Antennae usually saw- 

 toothed (serrate, Fig. 99). Some of these insects are preda- 

 ceous, but the greater number live within the stems or branches 

 of shrubs or trees. 



