THE LEGS. 47 



In bugs, the under lip forms a long sheath ; the 

 edges, bending downwards, are shaped into a hollow 

 canal, which receives the two pairs of jaws, in this case 

 formed like long bristles, the two middle ones pro- 

 bably acting as piercers, while the other two probably 

 assist in sucking. 



MEMBERS OF THE CORSELET. 



THE members which belong to the corselet are ap- 

 propriated to locomotion, and are of two sorts. One 

 sort are jointed to the under pieces of each of the three 

 rings of the corselet ; these are the legs ( ! ) : another 

 sort are jointed into the upper pieces of the mid cor- 

 selet and the hind corselet never to the fore corselet ; 

 these are the wings ( 2 ). 



Here the law of proportion is observed to regulate, 

 as it always does, the relative size of the members, 

 and the pieces on which they are jointed. When the 

 legs, or a pair of them accordingly are very short, the 

 corresponding pieces of the corselet are very small ; 

 and when the wings are small or wanting, the cor- 

 responding pieces are small or undivided. 



The Legs in Insects. 



Insects have exactly six legs, though the first pair 

 or the fore legs, are in some butterflies so small as 

 scarely to be detected. Millepedes, centipedes, and 

 wood-lice, which have more than six legs, are not 

 strictly insects. 



The fore legs, or first pair, are jointed into the 

 joinings of the breast-plate with the under flanks in 

 the fore corselet, and are always directed forwards. 



(l) In Latin, Pedes. (2) In Latin, Ales. 



