CHAP. III. THE LAEVA STATE. 21 



polished spots, termed piliferous spots, such as the Glassy Cut- 

 worm (Fig. 52; see the enlarged segment), from each of 

 which usually proceeds a fine hair. 



Many kinds of Iarva3 are entirely destitute of legs; these 

 are called grubs, maggots, etc.; for instance, the grub (Fig. 

 53) of the Plum Curculio; (Fig. 54) of the Flat-headed Apple- 



Fig. 53 



Fig. 54. 



Fig. 55. 



Fig. 56, 



Tree Borer; the grub (Fig. 55) of the Round-headed Apple- 

 Tree Borer; and the larva (Fig. 66) of the Hessian-fly * 



Others are provided with six legs, as the grubs or Iarva3 

 (Fig. 57) of the Ground-beetles. 



Fig. 57. 



Fig, 59. 



Larvae having from ten to sixteen legs are called true cater- 

 pillars, such as the Span-worms (Fig. 58), which have ten 

 legs; the Glassy Cut-worm (Fig. 52), which is provided 

 with sixteen legs. Caterpillars have a pair of horny legs 

 beneath each of the first three segments; these are the true 

 legs; the additional legs are fleshy, and are usually encircled 

 at the tips with a circle of minute hooks (Fig. 59); these 

 fleshy legs are commonly called prolegs, prop-legs, or false legs, 



The greater number of larva} which have more than the six 

 thoracic legs are furnished with ten prolegs (Fig. 52); these 

 are arranged in pairs beneath the sixth, seventh, eighth, ninth, 



