They were not much larger than the common English ant, of a dark brown colour. David, jumping down, caught one, and showed us that he had a sharp head, terminating in a pair of horizontal nippers--very like those of the warrior ants. In taking one up another had caught hold of his little finger, and gave it a nip which drew blood. Senhor Silva told us that they usually traverse the country by day and night, in trains nearly half a mile long, though only a few inches wide, and, as it passes under the grass, presents the appearance of a huge snake. They also, like the warrior ants, have soldiers who march by the side of the regular column, and the instant any danger appears hurry forward, when the column is either halted or turned backward. Should the difficulty be removed, it again advances. One of their most curious proceedings is the formation by the soldiers of a perfect arch, into which thousands of them weave their bodies, expanding across the whole width of a path where danger is apprehended. Under the arch the females and the labourers who bear the larva; then pass in comparative safety. It is formed in the following manner. One ant stands upright, and then another climbs up and interlocks its feet with the fore-feet of the first, and then another climbs up, somewhat in the fashion of acrobats. Another couple form the base of the arch on the opposite side, and then others, stretching themselves longways, form what may be called transverse beams, to keep the two sides connected. When thus formed, the creatures hold together so tenaciously, that the whole could be lifted off the ground without breaking. If attacked, they spread themselves on the ground over a space of thirty or more feet, across which neither man nor beast can pass with impunity. It is difficult to force a horse through them; and a dog will never venture, unless the space is sufficiently narrow to enable him to cross by a bound. He knows well that, should he fall, they would set upon him; and, before many hours were over, in spite of his strength, entirely consume him. They have been known to attack horses and cattle shut up in a confined space, and to reduce them to skeletons in less than a couple of days. They sometimes enter a dwelling-house through a small hole, and literally take possession, proceeding across the floor, over the walls and ceilings. "When I resided in the Brazils," said Senhor Silva, as we stood surveying the ants at work, "I was one morning seated at breakfast with my wife and little boy, when I heard outside the house a great commotion, and in rushed a black servant carrying the cage of our favourite parrot in one hand and grasping a number of pet fowls in the other; while our negro girl, hurrying in from another direction, and catching up the lapdog, cried out, `See! they come--they come! Fly, senhor. Fly, my dear mistress--fly, or you will all be eaten up.' Looking down to the ground, towards which she was directing her alarmed