"If the top of a small, fresh hillock, one in which the thatching process is going on, be taken off, a broad cylindrical shaft is disclosed, at a depth about two feet from the surface. If this be probed with a stick, which may be done to the extent of three or four feet without touching bottom, a small number of colossal fellows will slowly begin to make their way up the smooth sides of the mine. Their heads are of the same size as those of the other class (worker major); but the front is clothed with hairs instead of being polished, and they have in the middle of the forehead a twin ocellus, or simple eye, of quite different structure from the ordinary compound eyes on the side of the head. This frontal eye is totally wanting in the other workers, and is not known in any other kind of ant. The apparition of these strange creatures from {188} the cavernous depths of the mine reminded one, when I first observed them, of the Cyclopes of Homeric fable. They were not very pugnacious, as I feared they would be, and I had no difficulty in securing a few with my fingers. I never saw them under any circumstances than those here related, and what their special functions may be I cannot divine." The naturalist traveller, in the midst of much that interests and delights him, has to put up with a great deal that is annoying, and Mr. Bates proved no exception to the rule. The first few nights when at Caripí, he was much troubled with bats; the room where he slept had not been occupied for several months, and the roof was open to the tiles and rafters: "On one night," he says, "I was aroused about midnight by the rushing noise made by vast hosts of bats sweeping about the room. The air was alive with them; they had put out the lamp, and when I relighted it, the place appeared blackened with the impish multitudes that were whirling round and round. After I had lain about well with a stick for a few minutes they disappeared amongst the tiles, but when all was still again they returned, and once more extinguished the light. I took no further notice of them and went to sleep. The next night several got into my hammock; I seized them as they were crawling over me, and dashed them against the wall. The next morning I found a wound, evidently caused by a bat, on my hip." Bats remind us of the vampire, a native of South America, concerning whose blood-sucking properties so much discussion has been from time to time raised. The vampire bat was very common at Ega; it is the largest of the South American species. Of this bat Mr. Bates writes: