COLEOPTEBA OR BEETLES. 145 



The above classification is the one now generally adopted, 

 and is followed in the excellent section on Insects by Dr Sharp 

 in ' The Cambridge Natural History.' ^ 



COLEOPTERA, 



OR Beetles. 



The Coleoptera or Beetles are characterised by possessing four 

 wings. The front pair are horny, and are called elytra ; they 

 close over and protect the second pair, which are folded up. 

 The elytra meet in a straight line (suture) down the middle of 

 the abdomen. The larvEe of Coleoptera are of two main types 

 — one typically represented by the wireworm (fig. 78), in which 

 the first three segments have each a pair of jointed legs ; the 

 other by the maggot-like grubs of the weevils (fig. 72), which 

 are footless, and usually more or less curved. The body is com- 

 posed of thirteen segments, including the head. Many, such 

 as the CicindelidcB, have peculiar organs for catching their prey. 

 The pupae are always inactive. The larvae feed upon animal life 

 (carnivorous) or vegetable life, and may even be parasitic, as in 

 the Stylopidce found on bees : many also feed upon decaying 

 matter, acting as scavengers {Necropliagi or Burying Beetles). 

 The pupae are sometimes enclosed in a cocoon, the parts of the 

 insect being always distinctly recognisable. 



In structure the beetles have the following peculiarities : The 

 mouth consists of an upper lip or labrum, two mandibles, which 

 are hard and horny, two maxillae with palps, and a movable 

 lower lip or labium, with two jointed labial palpi. The antennte 

 are very variable in form and the number of segments. The 

 pro-, meso-, and metathorax are all well developed ; but when 

 the elytra are closed, only the prothorax is seen, and a small 

 part of the mesothorax called the scutelluin, which fits between 



' Camb. Nat. Hist., vol. v. (Peripatus, Myriapoda, and Insecta), p. 172. 



K 



