GROWTH AND METAMORPHOSIS OF INSECTS. 37 



accompanying Figs. 31-36, the appendages bud out from 

 the under side of the primitive band, and antennas, jaws, 

 legs, ovipositor (or sting), and the abdominal feet of cater- 

 pillars are at first all alike. Soon the appendages begin to 

 assume the form seen in the larva, and just before the 



FIG. 35. Profile view of embryo 

 Honey-bee, lettering as in Fig 34. 

 BM, nervous cord; uG, brain; D, 

 digestive canal; sch, the oesophagus; 

 St, stigmatal openings of the tra- 

 cheal system; R, heart. After Bliit- 

 schli. 



,-am 



dl.... 



Of- 



FIG. 36. Embryo of the Louse, am, 

 serous membrane; db, amnion; as, 

 antennas; rfc, forehead. After Mel- 

 nikow. 



insect hatches the last steps in the elaboration of the larval 

 form are taken. 



As to the development of the internal organs, the nervous 

 system first originates; the alimentary canal is next formed; 

 and at about this time the stigmata and air-tubes arise as 



