A NATURALIST IN BRAZIL 



they had clambered up it, and their jaws were cHnched upon it, 

 and upon my trousers. These were the defensive forces of the Sauvas' 

 nest, the soldiers. Only with difficulty could these infuriated insects 

 be detached ; many of them allowed their bodies to be pulled in 

 two rather than release their hold, and some hours later, long after 

 I had returned home, I found some Sauva soldiers whose jaws were 

 still clinched on my umbrella. 



A Sauvas' nest is a large subterranean dwelling, extending many 

 yards in all directions. In the centre, like the crater of a volcano, 

 rises a yellow hill with an entrance-hole, surrounded by smaller 

 hills, like parasitic craters. All the galleries run down to an average 

 depth of a yard or more, where the real nest with its many chambers 

 begins, of which I shall presently have something to say. It appears 

 that the depth of the nest is that of the stratum of the subsoil in 

 which the temperature remains uniform. Under special circumstances 

 the Sauvas build their nests in a different manner; for example, 

 on a hillside near Olinda I found that the chambers lay at a con- 

 siderably greater depth, while on the shores of the lagoons of brackish 

 water they were nearer the surface, doubtless on account of the 

 danger of inundation. 



I have excavated several nests of the Sauva ant : not alone, of 

 course, for that would have been beyond my powers. The first 

 requisite is equanimity, for the Sauvas defend themselves when 

 attacked, and the bite of their soldiers draws blood. In the northern 

 portion of the State of Pernambuco twelve men once worked for 

 six hours with their mattocks, and even then they did not succeed 

 in exposing the whole of the nest. On the land of the agricultural 

 college of the monastery the students came to my assistance ; and 

 I admired the way in which these vaHant young men, with rolled-up 

 trousers, hewed and shovelled while the blood ran down their legs, 

 for the excavated city was naturally swarming with ants, and the 

 excitement of the soldiers was indescribable. One of the students 

 in particular, Edysio by name, was indefatigable, and always in the 

 best of tempers ; a most attractive type of Brazilian. 



When, after prolonged effort, one reaches the actual centre of the 

 nest, the mattock lays bare chamber after chamber, and one sees, 

 lying in the dark holes, lumps as big as one's fist, of a very loose 

 texture, and looking rather like sponges; but so fragile that when 

 one takes them out they immediately crumble into dust. The Sauva 

 has hundreds of such chambers ; all are connected by cross-galleries 

 of various diameters, so that the whole nest is Like a mine. 



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