736 



CLASS IV. INSECTA. 



species occurring as far north as southern Europe. The females bore irt 

 wood and bark by means of the sharp mandibles borne at the tip of the 

 rostrum. There is often a marked sexual dimorphism in the members 

 of this family. Eupsalis, Cyphagogus, etc. 



Fam. 83. Curculionidae. Antennae usually elbowed. No labrum. 

 Maxillary palps small and rigid and concealed within the mouth. The 

 weevils form an enormous cosmopolitan family of over 20,000 very 

 varied species. The larvae, which feed on plants and their products, are 

 white, plump grubs devoid of legs. They cause much loss to the agricul- 

 turist. Rhynchites (Fig. 469), etc., etc. 



Fam. 84. Scolytidae. Antennae clubbed and elbowed, maxillary 

 palps short and rigid, but the rostrum extremely short and broad. 



FIG. 469. The leaf-rolling of Rhynchites betulae. Britain. A female beetle, magnified ; 

 B the beetle forming the first incision on a leaf ; C the completed roll. (B and C after 

 Debey.) 



The anterior tibiae are often toothed. A large family of small somewhat 

 cylindrical beetles which with their larvae are usually found in galleries 

 bored beneath the bark of trees. The pattern of the galleries varies with 

 the species at work. The larvae are whitish, legless grubs. Scolytus 

 destructor is the well-known " Elm beetle." 



The following two families of Coleoptera do not fall within the limits 

 of any of the larger groups and Sharp treats them as an appendix. 



Fam. 85. Aglycyderidae. Three segments, the second lobed, to the 

 tarsi. No rostrum. The family consists of a few species of the single 

 genus Aglycyderes scattered over some of the islands of the globe. 



Fam. 86. Proterhinidae. Tarsi with three easily visible segments, 

 the second lobed ; a minute additional joint present at the base of the 

 terminal joint. The female has a rostrum, which hardly exists in the male. 

 A single genus Protcrhhms, found in the Hawaiian Islands, constitutes 

 this family. 



