ORDER COLEOPTERA : BEETLES 233 



generally soft, with its appendages free ; but some pupae make 

 rough cases, some are chrysalises, and some pupate in their 

 larval skin. 



The order is of tremendous importance to the agri- 

 culturist and forester ; certain species that infest stored and 

 shipped grain and dry provisions provide at times a problem 

 for the sanitary officer; and the medical officer must not 

 forget that many beetles are active scavengers, and that 

 there are numerous aquatic beetles which, both in the adult 

 and larval state, are predaceous, and therefore are to be 

 reckoned among the possible checks upon mosquito-larvae. 



The Coleoptera are commonly divided into seven sub- 

 orders, as follows : — 



(i) Lamellicornia (Lat. lamella = z. small plate; cornu = 

 horn, or antenna). The distal segments of the antennae 

 form a sort of comb or book of broad plates, which when 

 closed up give the antenna a clubbed appearance. All the 

 tarsi are composed of 5 segments. 



(2) Adephaga (aSrjv^ to satiety, and ^ayeri' = to eat). 

 Antennae filiform ; outer lobe of maxilla often divided into 

 a two-jointed palp, the true maxillary palp being present 

 also. All the tarsi are composed of 5 segments. 



(3) Clavicornia (Lat. clava = a club, and cornu = antenna). 

 Antennae usually clubbed, the terminal joints not being 

 lamellate. 



(4) Serricornia (^2X. serra = 2. sa.w, and cornu). Antennae 

 usually toothed along the inner border. 



(5) Heteromera (eTe|Oo? = different; fxkpo^ = a part, or seg- 

 ment). There are 5 tarsal segments in the first and second 

 pairs of legs, and only 4 in the third pair. 



(6) Phytophaga {(purov — a tree; ^ayerj' = to eat). The 

 tarsi appear to be composed of 4 segments, the true 4th 

 segment being reduced and invisible in a dorsal view. Head 

 not produced into a snout. 



(7) Rhynchophora (/ouyxo? = a snout ; i^opkui = I carry). 

 Head usually produced into a snout. The tarsi usually appear 

 to consist of 4 segments, the true 4th segment usually 

 being reduced and hidden beneath the base of the true Sth. 



Of the Lamellicornia only the Scarabaidce (Fig. 99) 



