CHAP. III. THE LARVA STATE. 



19 



worm (Fig. 44), the Army- worm (Fig. 45), the Wire-worm 

 (Fig. 46), and the larva of the Lace-winged Fly (Fig. 47). 



Fig. 45. 



Fig. 46. 



The bodies of those larvae which are worm-like are divided 

 by transverse, depressed circles, generally into twelve parts^ 

 called "rings" or "segments." The first three segments near- 

 est the head (Fig. 48, B), represent the thorax of the perfect 

 insect, and are therefore termed "thoracic" segments; the re- 

 maining nine segments (Fig. 48, C), represent the abdomen of 

 the perfect insect, and are therefore designated the "abdominal" 

 segments. On the top of the segment next to the head (or the 

 first segment) is sometimes a horny plate (Fig. 48, G); this 

 plate is named the "cervical shield;" a plate of similar text- 

 ure on the last or anal segment (Fig. 48, F), when present, is 

 termed the "anal plate." Sometimes there is a horn or spine 

 on the top of the eleventh segment (Fig. 48, E); this is known 

 as the "anal horn." 



Fig. 47 



Fig. 48. 



Most of the larvae have nine spiracles, or breathing pores 

 (Fig. 48, H), on each side of the body, one on each side of the 

 first segment, and one on each side of the segments from four 

 to eleven inclusive. 



When there is a line of any color extending along the spi- 

 racles, it is termed the stigmata line. The back of a larva is 

 termed the dorsum, and when there is a line in the middle, 

 extending lengthwise with the body, it is termed the dorsal line. 



