M 



digestion, vascular system, respiratory system, repro- 

 ducing systera, nervous system. 



ORGAKS OF LOCOMOTION. 



The caterpillar of tlie moth and butterfly has always 

 eight, and never more than sixteen legs — one pair is placed, 

 as I have told you, upon the 2nd, 3rd, and 4th segments 

 (these are always present, and are called true legs) ; on the 

 7th, 8th, 9th, 10th, these may altogether be absent, as in 

 looping larva, or only one or more pairs, the missing ones 

 being absent always in pairs and commencing from th& 

 seventh segment, proceeding backwards. The last pair of 

 legs is seated on the 13th segment and is never absent; 

 these are called false or membranous legs. The iirst three 

 pairs of legs are called the pro legs, fore legs, or Thoracic 

 legs ; the four next are called the abdominal legs ; the last 

 pair the anal legs. 



If we examine the pro legs we shall find them short, 

 jointed, and conical, the apex terminating in a hook. These 

 legs are never used except when the larva is in progression; 

 they are employed to catch the uneven surfaces over which 

 the insect has to walk. "When at rest these hooks are 

 turned inwards and join those on the other side ; the head 

 dropping forward rests upon the first pair, as you can per- 

 ceive in the numerous specimens before you. 



The abdominal legs, when present, are of more use ; 

 they are membranous, short, thick, and conical, with the 

 apex cut off, so as to leave a broad base for the insect to 

 walk upon. It is in the sphinx larva (of which there are 

 several in the room) composed of two pieces somewhat 

 semi-circular, both edged with a row of fine sharp hooks, 

 the external ones directed inwards, the internal one* 

 directed outwards. They can walk flat footed, or have the 

 power of turning their legs inwards, so that by touching 

 the opposite foot can compress between the two small 

 twigs, up which they ascend to feed upon the leaves. The 

 snal foot is somewhat similarly formed, but is larger and 



