454 J. C. BRANNER — GEOLOGIC WORK OF ANTS 



sonal experience of them. It therefore seems best to quote directly a few 

 more detailed statements regarding the abundance and habits of ants in 

 Brazil. Certainly no one will be taken more seriously than Dr. Auguste 

 Forel, who says that "the ant fauna of South America is perhaps the 

 richest in the world from the systematic point of view.'^^^ In the paper 

 cited 440 species of true ants are noted as inhabiting Brazil, out of a total 

 of 2,000 known in the world. 



But though it is with the number of individuals rather than the num- 

 ber of species that we are concerned, it is worth remembering that in 

 many considerable regions a single species may occupy about all the 

 ground space that it is possible for ants to occupy. A single species may 

 thus fairly swarm and do a vast deal more work than several different 

 species. 



The true ants, evidently of a large number of species, are so abundant 

 and are such serious pests in some places that the land is practically pre- 

 empted by them. Travelers passing the night in the open have to be 

 constantly on their guard against colonies of ants. Fighting such colo- 

 nies under the circumstances is simply out of the question. When one 

 finds himself in disagreeable proximity to them, the only thing to be done 

 is to move at once and leave the ants masters of the situation. 



Bates, speaking of a certain species, says (page 354) : 



"These Ecitons are seen in the pathways of the forest at all places on the 

 banks of the Amazons, traveling in dense coUinms of countless thousands." 



On the Eio Tapajos, in the xVmazon Valley, Bates noted the 



"quantity of drowned winged ants along the beach ; they were all of one spe- 

 cies, the terrible formiga de fogo (Myrmica swvissima), the dead or half-dead 

 bodies of which were heaped up in a line an inch or two in height and breadth, 

 the line continuing without interruption for miles at the edge of the water. 

 The countless thousands had been doubtless cast into the river while flying 

 during a sudden squall the night before, and afterwards cast ashore by the 

 waves."^' ... "I was told that this wholesale destruction of ant-life takes 

 place annually, and that the same compact heap of dead bodies which I saw 

 only in part extends along the banks of the river for 12 or 15 miles" (op. clt., 

 p. 206). 



I have seen similar accumulations of dead female ants on the lower 

 Sao Francisco and the Eio Paraguay, near Corumba, and at two places 

 on the shores of estuaries near Aracaju, in the State of Sergipe. 



Bates says the formiga de fogo, or fire ant, was so abundant at one 



"A. Forel : A fauna das formigas do Brazil. Bol. do Museu Paraense, vol. 1, p. 89. 

 rara. 1895. 



^ H. W. Bates : The naturalist on the River Amazons, 4th ed., p. 201. London, 1875. 



