366 



ARTICULATES : INSECTS. 



repeatedly casts off its skin, and appears after each such 

 process with longer wings and limbs more completely 

 developed, until at length it ceases to grow, and, shed- 

 ding its skin for the last time, it comes forth a fully grown 

 insect, an adult grasshopper. The larvae and pupae of 

 those insects which undergo only a partial transforma- 

 tion have six legs, the same number as adult insects. Of 

 the larvae that undergo a complete transformation, some 

 have no legs, as maggots ; others have six, a pair to each 

 of the first three segments ; others still, as caterpillars, 

 have six true legs attached to the first three segments, 

 and, besides these, several fleshy legs, sometimes number- 

 ing ten or more, placed beneath the abdominal segment, 

 and known as prop-legs. The two sexes of insects differ 

 in size, the female being larger than the male, and 'in 

 many cases the former appears to have one ring less than 

 the latter, since the terminal ring is obsolescent, or forms 

 a small portion of the ovipositor. 



Insects proper are divided into seven sub-orders, and, 

 following the arrangement of A. S. Packard, Jr., in " Syn- 

 thetic Types of Insects," these stand as follows : 



Hymenoptera, or Membranous-winged Insects, as Bees, 

 Wasps, Ichneumons, Saw-Flies, Ants, and their allies ; 



Fig. 256. 



Fig. 257. 



Fig. 259. 



Figs. 256-258, Bees. 



Saw-Fly. 



