24 



PAKA. 



Chap. I. 



vary in size from two to seven lines ; some idea of them 

 may be obtained from the accompanying wood-cut. 

 The true working-class of a colony is formed by the small- 



Saliba or Leaf-cairying ant. — 1, Worker-minor ; 2, Worker-major ; 

 3, Subterranean worker. 



sized order of workers, the worker-minors as they are 

 called (Fig. 1). The tw^o other kinds, whose functions, 

 as we shall see, are not yet properly understood, have 

 enormously swollen and massive heads ; in one (Fig. 2), 

 the head is highly polished ; in the other (Fig. 3), it is 

 opaque and hairy. The worker-minors vary greatly in 

 size, some being double the bulk of others. The entire 

 body is of very solid consistence, and of a pale reddish- 

 brown colour. The thorax or middle segment is armed 

 with three pairs of sharp spines ; the head, also, has a 

 pair of similar spines proceeding from the cheeks behind. 

 In our first walks we were puzzled to account for 

 large mounds of earth, of a different colour from the 

 surrounding soil, which were thrown up in the planta- 

 tions and woods. Some of them were very extensive, 

 being forty yards in circumference, but not more than 



