The Naturalist in Nicaragua

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h my boxes we were rather uncomfortably crowded for a long journey. The canoe itself was made from the trunk of a cedar-tree (Cedrela odorata). It had been hollowed out of a single log, and the sides afterwards built up higher with planking. This makes a very strong boat, the strength and thickness being where it is most required, at the bottom, to withstand the t

addles with the greatest dexterity and force, made the canoe shoot along through the still water. Soon we emerged into a wider channel where a stronger stream was running, and then we coasted along close to the shore to avoid the strength of the current. The banks at first were low and marshy and intersected by numerous channels; the principal tree was a long, coarse-leaved palm, and there were great beds of wild cane and grass, amongst which we occasionally saw curious green lizards, with leaf-like expansions (like those on the leaf-insects), assimilating them in appearance to the vegetation amongst which they sought their prey. As we proceeded up the river, the banks gradually

writing in 1873) there is twelve feet of water on the bar at the Colorado in the height of the dry season, whilst at Greytown the outlet of the river is sometimes closed altogether. The merchants at Greytown have entertained the project of dredging out the channel again, but now that the river has found a nearer way to the sea by the Colorado this would be a herculean task, and it would cost much less money to move the whole town to the Colorado, where by dredging the bar a fine harbour might easily be made, but unfortunately the Colorado is in Costa Rica, the Greyt

hing out the delta further and further at this point, until it was greatly in advance of the rest of the coast; the river would then break through again by some nearer channel, and the Colorado wou

oes, which came off in myriads to the banquet upon our blood. Sleep for me was impossible, and to add to the discomfort, the rain came down in torrents. We had an old tarpaulin with us, but it was full of

e passed more open spots, affording glimpses into the forest, where grew, in the dark shade, slender-stemmed palms and beautiful tree-ferns, contrasting with the great leaves of the Heliconiae. At seven we breakfasted on a sand-bank, and got our clothes and blankets dried. There were numerous tracks of alligators, but it was too early to look for their eggs in the sand; a month later, in March, when the river falls, they are found in abundance, and eaten by the canoe-men. At noon we reached the point where the Seripiqui, a

o side, until it was nearly at right angles to its body. I afterwards saw other species in the forests and savannahs of Chontales. They all have several characters in common, linked together in a series of gradations. One of these features is a spot of black feathers on the breast. In some species this is edged with blue, in others, as in the one mentioned above, these black feathers form only a sma

HEADS OF

legs and mangled bodies of insects that they had captured in their foray. I afterwards often encountered t

OR FORA

d, they have to change their hunting-grounds when one is exhausted, and move on to another. In Nicaragua they are generally called "Army Ants." One of the smaller species (Eciton predator) used occasionally to visit our house, swarm over the floors and walls, searching every c

hes, grasshoppers, and spiders. The pursued insects would rapidly make off, but many, in their confusion and terror, would bound right into the midst of the main body of ants. A grasshopper, finding itself in the midst of its enemies, would give vigorous leaps, with perhaps two or three of the ants clinging to its legs. Then it would stop a moment to rest, and that moment would be fatal, for the tiny foes would swarm over the prey, and after a few more ineffectual struggles it would succumb to its fate, and soon be bitten to pieces and carried off to the rear. The greatest catch of the ants was, however, when they got amongst some falle

in advance, and apparently determined to put a good distance between themselves and their foe. I once saw one of the false spiders, or harvest-men (Phalangidae), standing in the midst of an army of ants, and with the greatest circumspection and coolness lifting, one after the other, its long legs, whi

s species closely resembles a green leaf, and the other senses, which in the Ecitons appear to be more acute than that of sight, must have been completely deceived. It might easily have escaped from the ants by using its wings, but it would only have fallen into as great a danger, for the numerous birds that accompany the army ants are ever on the look out for any insect that may fly up, and the heavy flying loc

n this duty. I have followed up these columns often; generally they led to dense masses of impenetrable brushwood, but twice they led me to cracks in the ground, down which the

The Ecitons hunt about in columns, which branch off in various directions. When a fallen log is reached, the column spreads out over it, searching through all the holes and cracks. The workers are of various sizes, and the smallest are here of use, for they squeeze themselves into the narrowest holes, and search out their prey in the furthest ramifications of the nests. When

aste and disorder; but the result of all this apparent confusion is that scarcely a single Hypoclinea gets away with a pupa or larva. I never saw the Ecitons injure the Hypoclineas themselves, they were always contented with despoiling them of their young. The ant that is attacked is a very cowardly species, and never shows fight. I often found it running about sipping

ards there are larger and lighter-coloured individuals that will often stop, and sometimes run a little backward, halting an

ches. Many of them are caught by the ants; others that get away are picked up by the numerous birds that accompany the ants, as vultures follow the armies of the East. The ants send off exploring parties up the trees, which hunt for nests of wasps, bees, and probably birds. If they find any, they soon communicate

th their heads ever turned to the only entrance, are in the best possible position to pick off singly the scouts when they approach, thus effectually preventing them from carrying to the main army intelligence about the nest. Some of these birds, and especially the toucans, hav

he females of many of the tree-rats and mice have a hard callosity near the teats, to which th

f the odours given off. I one day saw a column of Eciton hamata running along the foot of a nearly perpendicular tramway cutting, the side of which was about six feet high. At one point I noticed a sort of assembly of about a dozen individuals that appeared in consultation. Suddenly one ant left the conclave, and ran with great speed up the perpendicular face of the cutting without stopping. It was followed by others, which, however, did not keep straight on like the first, but ran a short way, then returned, then again followed a little further than the first time. They were evidently scenting the trail of the pioneer, and making it permanently recognisable. These ants followed the exact line

one place. I have sometimes come across the migratory columns. They may easily be known by all the common workers moving in one direction, many of them carrying the larvae and pupae carefully in their jaws. Here and there one of the light-coloured o

ained hundreds of thousands of individuals, although many columns were outside, some bringing in the pupae of ants, others the legs and dissected bodies of various insects. I was surprised to see in this living nest tubular passages leading down to the centre of the mass, kept open just as if it had been formed of inorganic materials. Down these holes the ants who were bringing in booty passed with their prey. I thrust a long stick down to the centre of the cluster, and br

ervals. I confined one of these under a piece of clay, at a little distance from the line, with his head projecting. Several ants passed it, but at last one discovered it and tried to pull it out, but could not. It immediately set off at a great rate, and I thought it had deserted its comrade, but it had only gone for assistance, for in a short time about a dozen ants came hurrying up, evidently fully informed of the circumstances of the case, for they made directly for their imprisoned comrade, and soon set him free. I do not see how this action could be instinctive. It was sympathetic help, such as man only among the higher mammalia shows. The excitement and ardour with which they carried on their unflagging exertions for the rescue of their comrade could not have been

ng a small branch, not thicker than a goose-quill. They widened this natural bridge to three times its width by a number of ants clinging to it and to each other on each side, over which the column passed three or four deep. Except for this expedient they would have had to pass over in single file, and treble the time would have been consumed. Can it not be contended that such insects are able to determine by reasoning po

ing, one in the Ants; the other in the Primates) run parallel. The Hymenoptera and the Mammalia both make their first appearance early in the secondary period, and it is not until the commencement of the tertiary e

e young, and all imbued with the strongest sense of industry, each individual labouring not for itself alone but also for its fellows-we may imagine that Sir Thomas More's description of Utopia might have been applied with greater justice to such a community than to any human society. "But in Utopia, where every man has a right to everything, they do all know that if care is taken to keep the public stores full, no private man can want anything; for among them there is no unequal distribution, so that no man is poor, nor