i6 



PARA 



insects, and proceed at once to the ants. These were in 

 great numbers everywhere, but I will mention here only- 

 two kinds. We were amazed at seeing ants an inch and 

 a quarter in length, and stout in proportion, marching 

 in single file through the thickets. These belonged to 

 the species called Dinoponera grandis. Its colonies con- 

 sist of a small number of individuals, and are established 

 about the roots of slender trees. It is a stinging species, 

 but the sting is not so severe as in many of the smaller 

 kinds. There was nothing peculiar or attractive in the 

 habits of this giant among the ants. Another far more 

 interesting species was the Saiiba (GEcodoma cephalotes). 

 This ant is seen everywhere about the suburbs, marching 

 to and fro in broad columns. From its habit of despoiling 

 the most valuable cultivated trees of their foliage, it is a 

 great scourge to the Brazilians. In some districts it is 

 so abundant that agriculture is almost impossible, and 

 everywhere complaints are heard of the terrible pest. 



The workers of this species are of three orders, 

 and vary in size from two to seven lines. The 

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

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

 called. The two other kinds, whose functions, as we 

 shall see, are not yet properly understood, have enor- 

 mously swollen and massive heads ; in one, the head is 

 highly polished ; in the other, 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 plantations 

 and woods. Some of them were very extensive, being 

 forty yards in circumference, but not more than two feet 

 in height. We soon ascertained that these were the work 

 of the Saiibas, being the outworks, or domes, which over- 

 lie and protect the entrances to their vast subterranean 

 galleries. On close examination, I found the earth of 

 which they are composed to consist of very minute 

 granules, agglomerated without cement, and forming 

 many rows of little ridges and turrets. The difference 



