174 



INVEUTEBEATE ANIMALS. 



a chamber placed in the centre of the nest. Both are without wings 

 and are much larger than the bulk of the community, the queen 

 immensely so, owing to the enormous distension of her abdomen 

 with eggs. The ordinary Termites are all sexless, incapable of lay- 

 ing eggs, and they are divided into two distinct sets or " castes," 



Fig. 120. — Different individuals of tlie colony of one of tlie Termites. A, The queen, 

 before the wings are shed ; D, The queen, after the wings are thrown off and the 

 abdomen has become greatly distended with eggs ; C, Worker ; B, Soldier. 



both destitute of wings, and differing in the armature of the head. 

 The one class includes the so-called " workers," who perform all the 

 ordinary work of the colony, whilst the " soldiers " have greatly 

 developed jaws, and are simply occupied in defending the nest 

 against all enemies. 



Section III. Holometabola. — Jfi'tamorphosis compUi.e ; the larva, 

 piip'-t, and imago differiiijj (/rcatb/ from one another in external ap- 

 pearance. The lari-a worm-lile, and the pupa quiescent. 



Order YIII. Aphaxiptera. 



In this order are only the Fleas {I'ldicidte) in which the mouth is 

 suctorial, the metamorphosis is complete, and the wings are rudi- 



