16 ROMANCE OF THE INSECT WORLD CHAP. 



within tlje one which immediately precedes it. Thus 

 their number becomes diminished, yet a segment 

 never entirely disappears, but invariably leaves 

 trace, however faint, of its former distinction. So 

 far as can be ascertained, the second, third, and 

 fourth rings of the larva go to form the thorax of 

 the perfect insect, the remaining nine constitute its 

 abdomen. The fifth however enters in part into the 

 composition of the thorax and forms the connection 

 of that portion with the abdominal region. It is 

 frequently atrophied,* and has almost entirely disap- 

 peared. If this piece be excluded, the abdomen is 

 composed of eight segments. Any deviation from 

 the rule in regard to reduced numbers will be found 

 to be apparent and not real. 



The larvae of some insects are entirely destitute of 

 legs and feet, as in the bee family and among flies, 

 and the body is otherwise modified where power of 

 locomotion is required. Many larvae, however, possess 

 pedal* appendages of two classes. These are true 

 legs, six in number, arranged in pairs, always on the 

 three segments of the thorax. So-called false or 

 abdominal legs are attached to the segments of 

 the .abdomen, their number ranging from a single 

 couple even to eight pairs. The true or thoracic 

 legs of young insects are very small and scale-like, 

 and are distinguished from the false legs by distinct 

 articulations or joints, by their strength and firmness 

 of texture, and their general pointed form. The 

 whole of these thoracic legs in all larvae that possess 

 them are nearly equally developed. In structure 

 and appearance the false legs are totally different. 



