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Sometimes I tried to chase one of them up to a corner where on the wall a large cockroach-eating spider stood motionless, looking out for his prey; the cockroach would rush away from me in great fear; but as soon as it came within a foot of its mortal foe nothing would force it onwards, but back it would double, facing all the danger from me rather than advance nearer to its natural enemy.
To return to the spiders. Besides the large owner and manufacturer of each web who was stationed near its centre, there were on the outskirts several very small ones, belonging, I think, to two different species. I sometimes threw a fly into one of the webs. The large spider would seize it and commence sucking its blood. The small ones, attracted by the sight of the prey, would advance cautiously from the circumference, but generally stop short about half-way up the web, evidently afraid to come within reach of the owner; thus having to content themselves with looking at the provisions, like hungry urchins nosing the windows of an eating-house. Sometimes a more audacious one would advance closer, but the owner would, when it came within reach, quickly lift up one of its feet and strike at it, like a feeding horse kicking at another that came near its provender, and the intruder would have to retire discomfited. These little spiders probably feed on minute insects entangled in the web, too small for the consideration of the huge owner, to whom they may be of assistance in clearing it.
Soon after crossing the muddy Artígua below Pavon, a beautifully clear and sparkling brook is reached, coming down to join its pure waters with the soiled river
below. In the evening this was a favourite resort of many birds that came to drink at the pellucid stream, or catch insects playing above the water. Amongst the last was the beautiful blue, green, and white hummingbird (Florisuga mellivora, Linn.); the head and neck deep metallic-blue, bordered on the back by a pure white
collar over the shoulders, followed by deep metallicgreen; on the underside the blue neck is succeeded by green, the green from the centre of the breast to the end of the tail by pure white; the tail can be expanded to a half circle, and each feather widening towards the end makes the semicircle complete around the edge. When catching the ephemeridæ that play above the water, the tail is not expanded: it is reserved for times of courtship. I have seen the female sitting quietly on a branch, and two males displaying their charms in front of her. One would shoot up like a rocket, then suddenly expanding the snow-white tail like an inverted parachute, slowly descend in front of her, turning round gradually to show off both back and front. The effect was heightened by the wings being invisible from a distance of a few yards, both from their great velocity of movement and from not having the metallic lustre of the rest of the body. The expanded white tail covered more space than all the rest of the bird, and was evidently the grand feature in the performance. Whilst one was descending, the other would shoot up and come slowly down, expanded. The entertainment ended in a fight between the two performers; but whether the more beautiful or the more pugnacious were the accepted suitor, I know not. Another fine humming-bird seen about this brook was the long-billed, fire-throated Heliomaster pallidiceps, (Gould), generally engaged in probing long narrowthroated red flowers, forming, with their attractive nectar, complete traps for the small insects on which the humming-birds principally feed, the bird returning the favour by carrying the pollen of one flower to another. A third species, also seen at this brook, Petasophora delphine, Less., is of a dull brown colour, with brilliant purple ear-feathers and metallic-green throat. Both it and Florisuga mellivora are short billed, generally catching flying insects, and do not frequent flowers so much as other humming-birds. I have seen the Petasophora fly into the centre of a dancing column of midges and
rapidly darting first at one and then at another secure half-a-dozen of the tiny flies before the column was broken up; then retire to a branch and wait until it was re-formed, when it made another sudden descent on them. A fourth species (Heliothrix barroti, Bourc.), brilliant green above, white below, with a shining purple crest, has also a short bill, and I never saw it about flowers, but always hovering underneath leaves and searching for the small soft-bodied spiders that are found there. Two of them that I examined had these spiders in their crops. I have no doubt many humming-birds suck the honey from flowers, as I have seen it exude from their bills when shot, but others do not frequent them. The principal food of all is small insects. I have examined scores of them, and without finding insects in their crops. Their generally long bills have been spoken of by some naturalists as tubes into which they suck the honey by à pistonlike movement of the tongue; but suction in the usual way would be just as effective; and I am satisfied that this is not the primary use of the tongue, nor of the mechanism which enables it to be exserted to a great length beyond the end of the bill. The tongue, for one-half of its length, is semi-horny and cleft in two,
Tongue of Humming-bird, with the blades a little opened.'
the two halves are laid flat against each other when at rest, but can be separated at the will of the bird and form a delicate pliable pair of forceps, most admirably adapted for picking out minute insects from amongst the
stamens of the flowers. The woodpecker, which has a similar extensile mechanism for exserting its tongue to a great length, also uses it to procure its food—in its case soft grubs from holes in rotten trees—and to enable it to pull these out, the end of the tongue is sharp and horny, and barbed with short stiff recurved bristles.
Tongue of large red-crested Woodpecker.
Continuing down the river, the road again crosses it, and enters on the primeval forest almost untouched by the hand of man, excepting in spots where the trees that furnish the best charcoal have been cut down by the charcoal-burners, or a gigantic isolated cedar (Cedrela odorata) has been felled for shingles, bringing down in its fall a number of the neighbouring trees entangled in the great bush ropes. Such open spots, letting in the sunshine into the thick forests, were favourite stoppingplaces; for numerous butterflies frequent them, all beautiful and most varied in their colours and marking. The fallen trees, too, are the breeding-places of multitudes of beetles, whose larvæ riddle them with holes. Some beetles frequent different varieties of timber, others are peculiar to a single tree. The most noticeable of these beetles are the numerous longicorns, to the collection of which I paid a great deal of attention, and brought home more than three hundred species. More than one-half of these were new to science, and have been described by Mr. Bates. To show how prolific the locality was in insect life, I need only state that about two hundred and ninety of the species were taken within