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its perseverance, and thought it would have given up the search ; not so, however, for it returned at least half-a-dozen times, and seemed to get angry, hurrying about with buzzing wings. At last it stumbled across its prey, seized it eagerly, and as there was nothing more to come back for, flew straight off to its nest, without taking any further note of the locality. Such an action is not the result of blind instinct, but of a thinking mind; and it is wonderful to see an insect so differently constructed using a mental process similar to that of man. It is suggestive of the probability of many of the actions of insects that we ascribe to instinct being the result of the possession of reasoning powers.
Where the tramway terminated at San Benito mine, the valley had greatly contracted in width, and the stream, excepting in time of flood, had dwindled to a little rill. A small rough path, made by the miners to bring in their timber, continued up the brook, crossing and recrossing it. The sides of the valley were very steep, and covered with trees and undergrowth. The foliage arched over the water, forming beautiful little dells, with small, clear pools of water. One of these was a favourite resort of humming-birds, who came there to bathe, for these gem-like birds are very frequent in their ablutions, and I spent many a half-hour in the evenings leaning against a trunk of a tree that had fallen across the stream four or five yards below the pool, and watching them. At all times of the day they occasionally came down, but during the short twilight there was a crowd of bathers, and often there were two or three at one time hovering over the pool, which was only three feet across, and dipping into it. Some would delay their evening toilet until the shades of night were thickening, and it became almost too dark to distinguish them from my stand. Three species regularly frequented the pool, and three others occasionally visited it. The commonest was the Thalurania venusta (Gould), the male of which is a most beautiful bird,—the front of the head and shoulders glistening purple, the throat brilliant light green, shining in particular lights like polished metal, the breast blue, and the back dark green. It was a beautiful sight to see this bird hovering over the pool, turning from side to side by quick jerks of its tail, now showing its throat a gleaming emerald, now its shoulders a glistening amethyst, then darting beneath the water, and rising instantly, throw off a shower of spray from its quivering wings, and fly up to an overhanging bough and commence to preen its feathers. All hummingbirds bathe on the wing, and generally take three or four dips, hovering, between times, about three inches above the surface.
Sometimes when the last-mentioned species was suspended over the water, its rapidly vibrating wings showing, like a mere film, a speck shot down the valley, swift as an arrow, as white as a snowflake, and stopping suddenly over the pool, startled the emerald-throat, and frightened it up amongst the overhanging branches. The intruder was the white-cap (Microchera parvirostris, Lawr.), the smallest of thirteen different kinds of humming-birds that I noticed around Santo Domingo; being only a little more than two and a half inches in length, including the bill; but it was very pugnacious, and I have often seen it drive some of the larger birds away from a flowering tree. Its body is purplish-red,
NOTES OF HUMMING-BIRDS.
with green reflections, the front of its head flat, and pearly white, and, when flying towards one, its white head is the only part seen. Sometimes the green-throat would hold its ground, and then it was comical to see them hovering over the water, jerking round from side to side, eyeing each other suspiciously, the one wishing to dip, but apparently afraid to do so, for fear the other would take a mean advantage, and do it some mischief whilst under water; though what harm was possible I could not see, as there were no clothes to steal. I have seen human bathers acting just like the birds, though from a different cause, bobbing down towards the water, but afraid to dip their heads, and the idea of comicality arose, as it does in most of the ludicrous actions of animals, from their resemblance to those of mankind. The dispute would generally end by the green-throat giving way, and leaving the pugnacious little white-cap in possession of the pool.
Besides the humming-birds I have mentioned, there were four or five other small ones that we used to call squeakers, as it is their habit for a great part of the day to sit motionless on branches and every now and then to chirp out one or two shrill notes. At first I thought these sounds proceeded from insects, as they resemble those of crickets; but they are not so continuous. After a while I got to know them, and could distinguish the notes of the different species. It was not until then that I found out how full the woods are of humming-birds, for they are most difficult to see when perched amongst the branches, and when flying they frequent the tops of trees in flower, where they are indistinguishable. I have sometimes heard the different chirps of more than
a dozen individuals, although unable to get a glimpse of one of them, as they are mere brown specks on the branches, their metallic colours not showing from below, and the sound of their chirpings—or rather squeakings -being most deceptive as to their direction and distance from the hearer. My conclusion, after I got to know their voices in the woods, was that the bumming-birds around Santo Domingo equalled in number all the rest of the birds together, if they did not greatly exceed them. Yet one may sometimes ride for hours without seeing one. They build their nests on low shrubs—often on branches overhanging paths, or on the underside of the large leaves of the shrubby palm-trees. They are all bold birds, suffering you to approach nearer than any other kinds, and often flying up and hovering within two or three yards from you. This fearlessness is probably owing to the great security from foes that their swiftness of flight ensures to them. I have noticed amongst butterflies that the swiftest and strongest flyers, such as the Hesperido, also allow you to approach near to them, feeling confident that they can dart away from any threatened danger,-a misplaced confidence, however, so far as the net of the collector is concerned.
At the head of the tramway, near the entrance to the San Benito mine, we planted about three acres of the banks of the valley with grass. In clearing away the fallen logs and brushwoods, many beetles, scorpions, and centipedes were brought to light. Amongst the last was a curious species belonging to the sucking division of the Myriapods (Sugantia, of Brandt), which had a singular method of securing its prey. It is about three inches
long, and sluggish in its movements; but from its tubular mouth it is able to discharge a viscid fluid to the distance of about three inches, which stiffens on exposure to the air to the consistency of a spider's web, but stronger. With this it can envelop and capture its prey, just as a fowler throws his net over a bird. The order of Myriapoda is placed by systematists at the bottom of the class of insects; the sucking Myriapods are amongst the lowest forms of the order, and it is singular to find one of these lowly organised species furnished with an apparatus of such utility, and the numberless higher forms without any trace of it. Some of the other centipedes have two phosphorescent spots in the head, which shine brightly at night, casting a greenish light for a little distance in front of them. I do not know the use of these lights, but think that they may serve to dazzle or allure the insects on which they prey. We planted two kinds of grasses, both of which have been introduced into Nicaragua within the last twenty years. They are called Pará and Guinea grasses, I believe, after the places from which they were first brought. The former is a strong succulent grass, rooting at the joints; the latter grows in tufts, rising to a height of four to five feet. Both are greatly liked by cattle and mules; large bundles were cut every day for the latter whilst they were at work on the tramway, and they kept in good condition on it without other food. The natural, indigenous grass that springs up in clearings in the neighbouring forest is a creeping species, and is rather abundant about Santo Domingo. It has a bitter taste, and cattle do not thrive on it, but rapidly fall away in condition if confined to it. They do better when allowed to roam about the outskirts