248 



MANUAL OF ZOOLOGY. 



mastication. The labium also is provided with a tubular organ 

 the " spinneret " which communicates with two internal 

 glands, the functions of which are to furnish the silk, whereby 



Fig. 88. Large White Cabbage Butterfly (Pontia brassier), a Larva or Caterpillar ; 

 b Pupa or Chrysalis ; c Imago or perfect Insect. 



Fig. 89. Goat-moth (Cossus ligniperda) and Caterpillar. 



