134 ROMANCE OF THE INSECT WORLD CHAP. 



that they have never been thoroughly investigated, but 

 an idea of their size is obtained from the fact that once 

 when sulphur smoke was introduced into a nest it 

 issued at an outlet seventy yards distant. Mr. Bates 

 relates that a species has been known to excavate a 

 tunnel under the bed of the river Parahyba, in Brazil, 

 at a place where it was as broad as the Thames at 

 London Bridge. Galleries radiate from the dome in 

 all directions ; the nest also contains rounded chambers 

 about as large as a man's head. The entrances are 

 small and numerous and generally closed ; very rarely 

 the ants are seen at work upon the mounds. 



Popularly known as leaf-cutters, these ants arc a 

 veritable scourge in central and tropical America, 

 where they abound, and may constantly be observed 

 forming broad processionary columns on their way to 

 and from the scenes of the fearful havoc they commit, 

 persistently and laboriously abstracting quantities of 

 pieces of foliage from the trees as large as sixpenny 

 bits. Valuable cultivated plants suffer most from their 

 attacks, the orange, lemon, coffee, and mango espe- 

 cially. In some districts agriculture has been rendered 

 almost impossible in consequence, or has been 

 abandoned. Their mode of cutting off the bits of 

 leaves is very interesting. Equally attractive are the 

 insects when in order of procession, returning home 

 laden with their spoil like multitudes of animated 

 leaves, each workman marching along holding its 

 portion in its jaws erect by one of the edges. The 

 habit has obtained for them the name of Parasol Ants, 

 the burden being supposed to be carried to shield its 

 bearer from the sun (see Fig. 17). It is now ascertained 



