678 Bulletin American Museum of Natural History. [Vol. XXIIl, 



often entering houses and earning off various farinaceous substances, and 

 does not make mounds above its nests, but long winding passages, terminat- 

 ing in chambers similar to the common species and always, like them, three 

 parts filled with flocculent masses of fungus-covered vegetable matter, 

 amongst which are the ant-nurses and immature ants. When a nest is 

 disturbed, and the masses of ant-food spread about, the ants are in great 

 concern to carry away every morsel of it under shelter again; and some- 

 times, when I dug into a nest, I found the next day all the earth thrown 

 out filled with little pits that the ants had dug into it to get out the covered 

 up food. When they migrate from one part to another, they also carry 

 with them all the ant-food from their old habitations. That they do not 

 eat the leaves themselves I convinced myself, for I found near the tenanted 

 chambers, deserted ones filled with the refuse particles of leaves that had 

 been exhausted as manure for the fungus, and were now left, and served as 

 food for larvse of Staphylinida' and other beetles. 



"These ants do not confine themselves to leaves, but also carry off any 

 vegetable substance that they find suitable for groAving fungus on. They 

 are very partial to the inside white rind of oranges, and I have also seen 

 them cutting up and carrying oft' the flowers of certain shrubs, the leaves of 

 which they have neglected. They are very particular about the ventilation 

 of their underground chambers, and have numerous holes leading up to 

 the surface from them. These they open out or close up, apparently to 

 keep up a regular degree of temperature below. The great care they take 

 that the pieces of leaves they carry into the nest should be neither too dry 

 nor too damp, is also consistent with the idea that the object is the growth 

 of a fungus that requires particular conditions of temperature and moisture 

 to ensure its vigorous growth. If a sudden shower should come on, the 

 ants do not carry the wet pieces into the burrows, but throw them down 

 near the entrances. Should the weather clear up again, these pieces are 

 picked up when nearly dried, and taken inside; should the rain, however, 

 continue, they get sodden down into the ground, and are left there. On 

 the contrary, in dry and hot weather, when the leaves would get dried up 

 before they could be conveyed to the nest, the ants, Avhen in exposed situa- 

 tions, do not go out at all during the hot hours, but bring in their leafy 

 burdens in the cool of the day and during the night. As soon as the pieces 

 of leaves are carried in they must be cut up by the small class of workers 

 into little pieces. I have never seen the smallest class of ants carrying in 

 leaves; their duties appear to be inside, cutting them into smaller fragments, 

 and nursing the immature ants. I have, however, seen them running out 

 along the paths with the others; but instead of helping to carry in the 

 burdens, they climb on the top of the pieces which are being carried along 



