ii FOOD OF INSECTS 53 



and when a well-filled individual loses its grasp and 

 falls to the floor, it is generally incompetent to 

 recover its balance. To a certain extent the workers 

 evidently regard them as dependents, the light in 

 which they probably look upon the other members 

 of the hive. They even perform their toilet for them, 

 though the rotunds seem able to assist themselves. 



The outer wall of an ant's abdomen consists of 

 a series of chitinous segmental plates, ten in 

 number, five dorsal* and five ventral* ones, which 

 overlap one another like the tiles of a roof. These 

 plates alone are visible externally in an ordinary ant. 

 In all ants, however, they are laid upon (if I may 

 so speak) an inner coat, which is highly elastic, and 

 in ordinary excessive feeding this membrane is 

 stretched between the plates, forcing them apart, the 

 degree of separation varying with the amount of food 

 taken. In the case of the honey - bearers some 

 of the plates become isolated, appearing like little 

 brown transverse bars on the tersely-stretched and 

 lighter coloured wall. Dr. McCook supposes the 

 honey to be not contained within the stomach, but 

 in the crop, an abdominal portion of the oesopha- 

 gus. The result is that the crop becomes immensely 

 distended, and almost completely fills the cavity of 

 the abdomen, to the displacement of the stomach and 

 other digestive organs, which are pushed into small 

 space towards the anal extremity. Sir John Lubbock 

 mentions another species of honey-ant, which he 

 describes as Camponotus inflatus, from Adelaide, 

 Australia. In it a similar habit and modification 

 have been evolved. Since the rotunds are probably 



