THE INSECT WORLD. 



is the structure of the tarsi alone an absolute guide to the food 

 habits ; but if we turn to the antennae or feelers we obtain an 

 additional basis. 



Roughly speaking, the beetles, other than those already sepa- 

 rated off, may be divided into filicornia, or those in which the 

 antennae are more or less thread-like, and which are usually car- 

 nivorous ; clavicornia, in which they enlarge toward the tip or 

 terminate in a more or less marked club, which are rarely carniv- 

 orous and usually scavengers ; serricor7iia, where the joints are 

 somewhat flattened and widen toward the tip, so that one mar- 

 gin resembles to a greater or less degree the toothed edge of a 

 saw, which are feeders upon vegetation, as a rule ; larnelli- 

 cornia, in which there is a leaf-like club at tip, which are always 

 vegetable feeders ; and monilicornia, where the joints are more 

 or less oval or globular and set so as to appear like a string of 

 beads. 



The terms filicornia and monilicornia are not in general use at 

 the present time. The latter series has the hind tarsi four-jointed 

 and the anterior and middle five-jointed, whence they are now 

 termed Hetero^nera, or "different-jointed," to distinguish them 

 from the Isomera,'' where all feet have the same number of 

 segments. But they are not uniform in habit, so that the deter- 

 mination of an insect as belonging to this heteromerous series 

 does not at once determine whether it is friend or foe. For the 

 Jilicomia the term Adephaga is used, from the usually predaceous 

 habits. 



Following the usual order of systematic arrangement, a com- 

 prehensive statement of the differences is as follows : 



I. Series with the head not prolonged into a snout, true Coleoptera. 



a, The antennae filiform, or thread-like, the tarsi with five joints on 



all feet Adephaga. 



b, The antennae thickening outwardly into a more or less well-formed 



club, tarsi with an equal though varying number of joints on 

 all feet Clavicornia, 



c, The antennae serrate or saw-toothed, the tarsi usually five- 



jointed Serricornia. 



d, The antennae with a lamellate or leaf-like club at tip, the tarsi 



five-jointed Lamellicornia. 



e, The antennae somewhat variable, the tarsi four-jointed, the third 



deeply lobed or cleft Phytophaga. 



