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TROPICAL NATUREof rare butterflies and other insects, I laid it down on thebench by my side. On leaving the house I noticed some antson it,and on opening the box found only a mass of detachedwings and bodies, the latter in process of being devoured byhundreds of fire-ants.The celebrated Sauba ant of America (CEcodoma cephalotes)is allied to the preceding, but is even more destructive,though it seems to confine itself to vegetable products. Itforms extensive underground galleries, and the earth broughtup is deposited on the surface, forming huge mounds sometimesthirty or forty yards in circumference and from oneto three feet high.On first seeing these vast deposits ofred or yellow earth in the woods near Para, it was hardlypossible to believe they were not the work of man, or atleast of some large burrowing animal. In these undergroundcaves the ants store up large quantities of leaves, which theyobtain from living trees. They gnaw out circular pieces andcarry them away along regular paths a few inches wide,forming a stream of apparently animated leaves. The greatextent of the subterranean workings of these ants is no doubtdue in part to their permanence in one spot, so that whenportions of the galleries fall in or are otherwise rendereduseless, they are extended in another direction. When inthe island of Mara jo, near Para, I noticed a path along whicha stream of Saiibas were carrying leaves from a neighbouringthicket; and a relation of the proprietor assured me thathe had known that identical path to be in constant use bythe ants for twenty years. Thus we can account for thefact mentioned by Mr. Bates, that the underground gallerieswere traced by smoke for a distance of seventy yards in theBotanic Gardens at Para ;and for the still more extraordinaryfact related by the Eev. Hamlet Clark, that an allied speciesin Eio de Janeiro has excavated a tunnel under the bed ofthe river Parahyba, where it is about a quarter of a mile wide !These ants seem to prefer introduced to native trees ;and youngplantations of orange, coffee, or mango trees are sometimesdestroyed by them, so that where they abound cultivation ofany kind becomes almost impossible. Mr. Belt ingeniouslyaccounts for this preference by supposing that for ages therehas been a kind of struggle going on between the trees