8540 Notices of New Books. 



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 pro- 

 perly understood, have enormously swollen and massive heads. In 

 one the head is highly polished, in the other it is hairy and opaque. 

 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 has also 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 

 Saubas, being the outworks or domes which overlie 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 in colour from the superficial soil 

 of the vicinity is owing to their being formed of the undersoil, brought 

 up from a considerable depth. It is very rarely that the ants are seen 

 at work on these mounds ; the entrances seem to be generally closed, 

 only now and then, when some particular work is going on, are the 

 galleries opened. The entrances are small and numerous; in the 

 larger hillocks it would require a great amount of excavation to get 

 at the main galleries, but I succeeded in removing portions of the dome 

 in smaller hillocks, and then I found that the minor entrances con- 

 verged, at the depth of about two feet, to one broad elaborately worked 

 gallery or mine, which was four or five inches in diameter. 



" This habit in the Saiiba ant of clipping and carrying away immense 

 quantities of leaves has long been recorded in books on Natural 

 History. When employed on this work their processions look like a 

 multitude of animated leaves on the march. In some places I found 

 an accumulation of such leaves, all circular pieces, about the size of 

 a sixpence, lying on the pathway, unattended by ants, and at some 



