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their appearance suddenly in the dry forest near Ega, in large flocks, probably assemblages of birds gathered together from the neighboring Ygapó forests, which are then flooded and cold. The birds have now be come exceedingly tame, and the troops travel with heavy laborious flight from_boagh to bough among the lower trees. They thus become an easy prey to hunters, and every one at Ega who can get a guu of any sort and a few charges of powder and shot, or a blow-pipe, goes daily to the woods to kill a few brace for dinner; for, as already observed, the people of Ega live almost exclusively on stewed and roasted Toucans during the months of June and July, the birds being then very fat, and the meat exceedingly sweet and tender.

No one on seeing a Toucan can help asking what is the use of the enormous bill, which, in some species, attains a length of seven inches, and a width of more than two inches. A few remarks on this subject may be here introduced. The early naturalists having seen only the bill of a Toucan, which was esteemed as a marvellous production by the virtuosi of the sixteenth and seventeenth centuries, concluded that the bird must have, belonged to the aquatic and web-footed order, as this contains so many species of remarkable development of beak, adapted for seizing fish. Some travelers also related fabulous stories of Toucans resorting to the banks of rivers to feed on fish, and these accounts also encouraged the erroneous views of the habits of the birds which for a long time prevailed. Toucans, however, are now well known to be eminently arboreal birds, and to belong to a group (including trogons, parrots, and barbets ), all of whose menibers are fruit-eaters. On the Amazons, where these birds are very common, no one pretends ever to have seen a Toucan walking on the ground in its natural state, much less acting the part of a swimming or wading bird. Professor Owen found, on dissection, that the gizzard in Toucans is not so well adapted for the trituration of food as it is in other vegetable feeders, and concluded, therefore, as Broderip had observed the habit of chewing the cud in a tame bird, that the great toothed bill was useful in holding and re-masticating the food. The bill can scarcely be said to be a very good contriv. ance for seizing and crushing small birds, or taking them from their nests in crevices of trees, habits which have been imputed to Toucans by some writers. The hollow, cellular structure of the interior of the bill, its curved and clumsy shape, and the deficiency of force and precision when it is used to seize objects, suggest a want of fitness, if this be the function of the member. But fruit is undoubtedly the chief food of Toucans, and it is in reference to their mode of obtaining it that the use of their uncouth bills is to be songht.

Flowers and fruit on the crowns of the large trees of South American forests grow principally toward the end of slender twigs,

which will not bear any considerable weight; all animals, therefore, which feed upon food, or on insects contained in flowers, must, of course, have some means of reaching the ends of the stalks from a distance. Monkeys obtain their food by stretching forth their long arms, and, in some instances, their tails, to bring the fruit near to their mouths. Humming birds are endowed with highlyperfected organs of flight, with corresponding muscular development, by which they are enable 1 to sustain themselves on the wing before blossoms while rifling them of their contents. These strong-flying creatures, however, will, whenever they can get near enough, remain on their perches while probing neighboring flowers for insects. Trogons have feeble wings, and a dull, inactive temperament. Their mode of obtaining food is to station themselves quietly on low branches in the gloomy shades of the forest, and eye the fruits on the surrounding trees, darting off as if with an effort every time they wish to seize a mouthful, and returning to the same perch. Barbets (Capitonina) seem to have no especial endowment, either of habits or structure, to enable them to seize fruits; and in this respect they are similar to the Toucans, if we leave the bill out of question, both tribes having heavy bodies, with feeble organs of flight, so that they are disabled from taking their food on the wing. The purpose of the enormous bill here becomes evident. It is to enable the Toucan to reach and devour fruit while remaining seated, and thus to counterbalance the disadvantage which its heavy body and gluttonous appetite would otherwise give it in the competition with allied groups of birds. The relation between the extraordinarily lengthened bill of the Toucan and its mode of obtaining food, is therefore precisely similar to that between the long neck and lips of the Giraffe and the mode of browsing of the animal. The bill of the Toucan can scarcely be considered a very perfectly-formed instrument for the end to which it is applied, as here explained; but nature appears not to invent organs at once for the functions to which they are now adapted, but avails herself, here of one already-existing structure or instinct, there of another, according as they are handy when need for their further modification arises.

One day while walking along the principal pathway in the woods near Ega, I saw one of these Toucans seated gravely on a low branch close to the road, and had no difficulty in seizing it with my hand. It turned out to be a runaway pet bird; no one, however, came to own it, although I kept it in my house for several months. The bird was in a half-starved and sickly condition, but after a few days of good living it recovered health and spirits, and became one of the most amusing pets imaginable. Many excellent accounts of the habits of tame Toucans have been published, and therefore I need not describe them in detail, but I do not recollect to have seen any notice of their intelligence

and confiding disposition under domestication, in which qualities my pet seemed to be almost equal to parrots. I allowed Tocáno to go free about the house, contrary to my usual practice with pet animals; he never, however, mounted my working-table after a smart correction which he received the first time he did so. He used to sleep on the top of a box in a corner of the room, in the usual position of these birds, namely, with the long tail laid right over on the back, and the beak thrust underneath the wing. He ate of every thing that we eat, beef, turtle, fish, farinha, fruit, and was a constant attendant at our table-a cloth spread on a mat. His appetite was most ravenous, and his powers of digestion quite wonderful. He got to know the meal hours to a nicety, and we found it very difficult, after the first week or two, to keep him away from the dining-room, where he had become very impudent and troublesome. We tried to shut him out by inclosing him in the back yard, which was separated by a high fence from the street on which our front door opened, but he used to climb the fence and hop round by a long circuit to the dining-room, making his appear ance with the greatest punctuality as the meal was placed on the table. He acquired the habit afterward of rambling about the street near our house, and one day he was stolen, so we gave him up for lost. But two days afterward he stepped through the open doorway at dinner-hour, with his old gait and sly, magpie-like expression, having escaped from the house where he had been guarded by the person who had stolen him, and which was situated at the further end of the village.

The Curl-crested Toucan (Pteroglossus Beauharnaisii). Of the four sinaller Toucans, or Arassarís, found near Ega, the Pteroglossus flavirostris is perhaps the most beautiful in colors, its breast being adorned with broad belts of rich crimson and black; but the most curious species by far is the Curlcrested, or Beauharnais Toucan. The feathers on the head of this singular bird are transformed into thin horny plates, of a lastrous black color, curled up at the ends, and resembling shavings of steel or ebony wood, the curly crest being arranged on the crown in the form of a wig. Mr Wallace and I first met with this species on ascending the Amazons, at the mouth of the Solimoens; from that point it continues as a rather common bird ou the teria firma, at least on the south side of the river, as far as Fonte Boa, but I did not hear of its being found further to the west It appears in large flocks in the forests near Ega in May and June, when it has completed its moult. 1 did not find these bands congregated at fruit trees, but always wandering through the forest, hopping from branch to branch among the lower trees, and partly concealed among the foliage. None of the Arassarís to my knowledge make a yelping noise like that uttered by the larger Toucans (Ramphastos); the notes of the curl-crested species are very

singular, resembling the croaking of frogs. I had an amusing adventure one day with these birds. I had shot one from a rather high tree in a dark glen in the forest, and entered the thicket where the bird had fallen to secure my booty. It was only wounded, and on my attempting to seize it, set up a loud scream. In an instant, as if by magic, the shady nook seemed alive with these birds, although there was certainly none visible when I entered the jungle. They descended toward me, hopping from bough to bough, some of them swinging on the loops and cables of woody lianas, and all croaking and fluttering their wings like so many furies. If I had had a long stick in my hand, I could have knocked several of them over. After killing the wounded one, I be gan to prepare for obtaining more specimens and punishing the viragoes for their boldness but the screaming of their companion having ceased, they remounted the trees, and before I could reload every one of them had disappeared.

Insects.-Upward of 7000 species of insects were found in the neighborhood of Ega. I must confine myself in this place to a few remarks on the order Lepidoptera, and on the ants, several kinds of which, found chiefly on the Upper Amazons, exhibit the most extraordinary instincts.

But

I found about 550 distinct species of butterflies at Ega. Those who know a little of Entomology will be able to form some idea of the riches of the place in this department when I mention that eighteen species of trus papilio (the swallow-tail genus) were foun l within ten minutes' walk of my house. Nɔ fact could speak more plainly for the surpassing exuberance of the vegetation, the varied nature of the land, the perennial warmth and humidity of the climate. no description can convey an adequate notion of the beauty and diversity in form and color of this class of insects in the neighborhood of Ega. I paid especial attention to them, having found that this tribe was better adapted than almost any other group of animals or plants, to furnish facts in illustration of the modifications which all species undergo in nature under changed local conditions. This accidental superiority is owing partly to the simplicity and distinctness of the specific characters of the insects, and partly t the facility with which very copious series. of specimens can be collected and placed side by side for compariso The distinctness of“ the specific characters is due probably to the fact that all the superficial signs of change im the organization are exaggerated and made unusually plain by affecting the framework,. shape, and color of the wings, which, ass many anatomists believe, are magnified extensions of the skin around the breathing; orifices of the thorax of the insects. These. expansions are clothed with minute feathers; or scales, colored in regular patterns, which: vary in accordance with the slightest change in the conditions to which the species are ex

posed. It may be said, therefore, that on stick, and so made tubes similar to those of these expanded membranes nature writes, as caddice-worms; others (Saccophora) chose on a tablet, the story of the modifications of species, so truly do all changes of the organization register themselves thereon, More over, the same color-patterns of the wings geuerally show, with great regularity, the degrees of blood relationship of the species, As the laws of nature must be the same for all beings, the conclusions furnished by this group of insects must be applicable to the whole organic world; therefore the study of butterflies-creatures selected as the types of airiness and frivolity-instead of being despised, will some day be valued as one of the most important branches of biological science.

leaves for the same purpose, forming with them an elongated bag open at both ends, and having the inside lined with a thick web. The tubes of full-grown caterpillars of Saccophora are two inches in length, and it is at this stage of growth that I have generally seen them. They feed on the leaves of Melastoma, and as in crawling the weight of so large a dwelling would be greater than the contained caterpillar could sustain, the insect attaches the case, by one or more threads, to the leaves or twigs near which it is feeding.

Foraging Ants.-Many confused statements Before proceeding to describe the ants, a have been published in books of travel and few remarks may be made on the singular copied in natural history works regarding cases and cocoons woven by the caterpillars these ants, which appear to have been conof certain moths found at Ega. The first founded with the Saüba, a sketch of whose that may be mentioned is one of the most habits has been given in the first chapter of beautiful examples of insect workmanship I this work. The Satiba is a vegetable feeder, ever saw. It is a cocoon, about the size of and does not attack other animals; the aca sparrow's egg, woven hy a caterpillar in counts that have been published regarding broad meshes of either buff or rose-colored carnivorous ants which hunt in vast armies, silk, and is frequently seen in the narrow exciting terror wherever they go, apply only alleys of the forest, suspended from the ex- to the Ecitons, or foraging ants, a totally dif trem tip of an outstanding leaf by a strong ferent group of this tribe of insects. The silken thread five or six inches in length. It Ecitons are called Tauóca by the Indians, forms a very conspicuous object, hanging who are always on the lookout for their thus in mid-air. The glossy threads with armies when they traverse the forest, so as which it is knitted are stout, and the structure to avoid being attacked. I met with ten disis therefore not liable to be torn by the beaks tinct species of them, nearly all of which of insectivorous birds, while its pendulous have a different system of marching; eight position makes it doubly secure against their were new to science when I sent them to attacks, the apparatus giving way when they England. Some are found commonly in peck at it. There is a small orifice at each every part of the country, and one is peculiar end of the egg-shaped bag, to admit of the to the open campos of Santarem; but, as escape of the moth when it changes from the little chrysalis which sleeps tranquilly in its airy care. The moth is of a dull slaty color, and belongs to the Lithosiide groupe of the silk-worm family (Bombycidae). When the caterpillar begins its work, it lets itself down from the tip of the leaf which it has chosen, by spinning a thread of silk, the thickness of which it slowly increases as it descends. Having given the proper length to the cord, it proceeds to weave its elegant bag, placing itself in the centre and spinning rings of silk at regular intervals, connecting them at the same time, by means of cross-threads; so that the whole, when finished, forms a loose web, with quadrangular meshes of nearly equal size throughout. The task occupies about four days. When finished, the enclosed caterpillar becomes sluggish, its skin shrivels and cracks, and there then remains a motionless chrysalis of narrow shape, leaning against the sides of its silken cage.

Many other lands are found at Ega be longing to the same cocoon-weaving family, some of which differ from the rest in their caterpillars possessing the art of fabricating cases with fragments of wood or leaves, in which they live secure from all enemies while they are feeding and growing. I saw many species of these; some of them knitted together, with fine silken threads, small bits of

nearly all the species are found together at Ega, where the forest swarmed with their armies, I have left an account of the habits of the whole genus for this part of my narrative. The Ecitons resemble in their habits the Driver ants of tropical Africa; but they have no close relationship with them in structure, and indeed belong to quite another sub-group of the ant tribe.

Like many other ants, the commuuities of Ecitons are composed, besides males and females, of two classes of workers, a largeheaded (worker-major) and a small-headed (worker-minor) class; the large-heads have in some species greatly lengthened jaws, the small-beads have jaws always of the ordinary shape; but the two classes are not sharply defined in structure and function, except in two of the species. There is in all of them a little difference among the workers regard ing the size of the head; but in some species this is not sufficient to cause a separation into classes, with division of labor; in others the jaws are so monstrously lengthened in the worker-majors, that they are incapaci tated for taking part in the labors which the worker-minors perform; and again, in others the difference is so great that the disinction of classes becomes complete, one cting the part of soldiers, and the other that of workers. The peculiar feature in the

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habits of the Eciton genus is their hunting for prey in regular bodies or armies. It is this which chiefly distinguishes them from the genus of common red stinging ants, several species of which inhabit England, whose habit is to search for food in the usual irregular manner. All the Ecitons hunt in large, organized bodies; but almost every species has its own special manner of hunting.

Eciton rapax.-One of the foragers, Eciton rapax, the giant of its genus, whose workermajors are half an inch in length, hunts in single file through the forest. There is no division into classes among its workers, although the difference in size is very great, some being scarcely one half the length of others. The head and jaws. however, are always of the same shape, and a gradation in size is presented from the largest to the smallest, so that all are able to take part in the common labors of the colony. The chief employment of the species seems to be plundering the nests of a large and defenceless ant of another genus (Formica), whose mangled bodies I have often seen in their possession as they were marching away. The armies of Eciton rapax are never very nu

merous.

Eciton legionis.-Another species, E. legionis, agrees with E. rapax in having workers not rigidly divisible into two classes; but it is auch smaller in size, not differing greatly in this respect from our common English red ant (Myimica rubra), which it also resembles in color. The Eciton legionis lives in open places, and was seen only on the sandy campos of Santarem. The movements of its hosts were, therefore, much more easy to observe than those of all other kinds, which inhabit solely the densest thickets; its sting and bite also were less formidable than those of other species. The armies of E. legionis consist of many thousands of individuals, and move in rather broad columns. They are just as quick to break line on being disturbed, and attack hurriedly and furiously any intruding object, as the other Ecitous. The species is not a common one, and I seldom had good opportunities of watching its habits. The first time I saw an army was one evening near sunset. The column consisted of two trains of ants, moving in opposite directions; one train empty-handed, the other laden with the mangled remains of insects, chiefly larvæ and pupæ of other ants. I had no difficulty in tracing the line to the spot from which they were conveying their booty; this was a low thicket; the Ecitons were moving rapidly about a heap of dead leaves; but as the short tropical twilight was deepening rapidly, and I had no wish to be benighted on the lonely campos, I deferred further examination until the next day.

On the following morning no trace of ants could be found near the place where I had seen them the preceding day, nor were there signs of insects of any description in the thicket; but at the distance of eighty or one hundred yards, I came upon the same army,

engaged evidently on a razzia of a similar kind to that of the previous evening, but requiring other resources of their instinct, owing to the nature of the ground. They were eagerly occupied on the face of an inclined bank of light earth in excavating mines, whence, from a depth of eight or ten inches, they were extracting the boilies of a bulky species of ant of the genus Formica. It was curious to see them crowding round the orifices of the mines, some assisting theic comrades to lift out the bodies of the Formica, and others tearing them in pieces, on account of their weight being too great for a single Eciton, a number of carriers seizing each a fragment and carrying it off down the slope. Oa digging into the earth with a small trow near the entrance of the mines, I found the nests of the Formica, with grubs and cocoons, which the Ecitons were thus invading, at a depth of about eight inches from the surface The eager freebooters rushed in as fast as I excavated, and seized the ants in my fingers as I picked them out, so that I had some difficulty in rescuing a few entire for specimens. In digging the numerous mines to get at their prey, the little Ecitons seemed to be divided into parties, one set excavating and another set carrying away the grains of earth. When the shafts became rather deep, the mining parties ha to climb up the sides each time they wished to cast out a pellet of earth; bat their work was lightened for thein by comrades, who stationed themselves at the mouth of the shaft, and relieve them of their burdens, carrying the particles, with an appearance of foresight which quite staggered ine, a sufficient distance from the edge of the hole to prevent them from rolling in again. All the work seemed thus to be performed by intelligent co-operation among the host of eager little creatures; but still there was not a rigid division of labor, for some of them, whose proceedings I watched, acted at one time as carriers of pellets, and at another as miners, and all shortly afterward assumed the office of conveyers of the spoil.

In about two hours all the nests of Formice were rifled, though not completely, of their contents, and I turned toward the army of Ecitous, which were carrying away the mutilated remains. For some distance there were many separate lines of them moving along the slope of the bank; but a short distance off these all converged, and then formed one close and broad column, which continued for some sixty or seventy yards, and terminated at one of those large termìtariums or hillocks of white ants which are constructed of cemented material as hard as stone. The broad and compact column of ants moved up the steep sides of the hillock in a continued stream; many which had hitherto trotted along empty handed, now turned to assist their comrades with their heavy loads, and the whole descended into a spacious gallery or mine opening on the top of the termitarium. I did not try to reach the nest which

I supposed to lie at the bottom of the broad mine, and therefore in the middle of the base of the stony hillock.

Eciton drepanophora.-The commonest species of foraging ants are the Eciton hamata and E. drepanophora, two kinds which resemble each other so closely that it requires attentive examination to distinguish them; yet their armies never intermingle, although moving in the same woods and often crossing each other's tracks. The two classes of workers look, at first sight, quite distinct, on account of the wonderful amount of difference between the largest individuals of the one, and the smallest of the other. There are dwarfs not more than one fifth of an inch in length, with small heads and jaws, and giants half an inch in length, with monstrously enlarged head and jaws, all belong. ing to the same brood. There is not, how ever, a distinct separation of classes, individuals existing which connect together the two extremes. These Ecitons are seen in the pathways of the forest at all places on the banks of the Amazons, traveling in dense columns of countless thousands. One or other of them is sure to be met with in a woodland ramble, and it is to them, probably, that the stories we read in books on South America apply, of ants clearing houses of vermin, although I heard of no instance of their entering houses, their ravages being confined to the thickest parts of the forest.

When the pedestrian falls in with a train of these ants, the first sigual given him is a twittering and restless movement of small flocks of plain-colored birds (ant thrushes) in the jungle. If this be disregarded until he advances a few steps farther, he is sure to fall into trouble, and find himself suddenly attacked by numbers of the ferocious little creatures. They swarm up his legs with incredible rapidity, each one driving its pincerlike jaws into his skin, and with the purchase thus obtained, doubling in its tail and stinging with all its might. There is no course left but to run for it; if he is accompanied by natives, they will be sure to give the alarm, crying, "Tauóca!" and scampering at full speed to the other end of the column of ants. The tenacious insects who have secured themselves to his legs then have to be plucked off one by one, a task which is generally not accomplished without pulling them in twain, and leaving heads and jaws sticking in the wounds.

The errand of the vast ant-armies is plunder, as in the case of Eciton legionis but from their moving always among dense thickets their proceedings are not so easy to observe as in that species. Wherever they move, the whole animal world is set in commotion, and every creature tries to get out of their way. But it is especially the various tribes of winged insects that have cause for fear, such as heavy-bodied spiders, ants of other species, maggots, caterpillars, larvæ of cockroaches, and so forth, all of which live under fallen leaves, or in decaying wood. The Ecitons do not mount very high on

trees, and therefore the nestlings of birds are not much incommoded by them. The mode of operation of these armies, which I ascertained only after long-continued observation, is as follows. The main column, from four to six deep, moves forward in a given direction, clearing the ground of all animal matter, dead or alive, and throwing off here and there a thinner column to forage for a short time on the flanks of the main army, and reenter it again after their task is accomplished. If some very rich place be encountered anywhere near the line of march-for example, a mass of rotten wood abounding in insect larvæ a delay takes place, and a very strong force of ants is concentrated upon it. The excited creatures search every cranny and tear in pieces all the large grubs they drag to light. It is curious to see them attack wasps' nests, which are sometimes built on low shrubs. They gnaw away the papery covering to get at the larvæ, pupa, and newly hatched wasps, and cut everything to tatters, regardless of the infuriated owners which are flying about them. In bearing off their spoil in fragments, the pieces are apportioned to the carriers with some degree of regard to fairness of load, the dwarfs taking the smallest pieces, and the strongest fellows with small heads the heaviest portions. Sometimes two ants join together in carrying one piece, but the worker-majors, with their unwieldy and distorted jaws, are incapaci. tated from taking any part in the labor. The armies never march far on a beaten path, but seem to prefer the entangled thickets, where it is seldom possible to follow them. I have traced an army sometimes for half a mile or more, but was never able to find one that had finished its day's course and returned to its hive. Indeed, I never met with a hive ; whenever the Ecitous were seen they were always on the march.

i thought one day, at Villa Nova, that I had come upon a migratory horde of this indefatigable ant. The place was a tract of open ground near the river side, just outside the edge of the forest, and surrounded by rocks and shrubbery. A dense column of Ecitons was seen extending from the rocks on one side of the little haven, traversing the open space, and ascending the opposite de clivity. The length of the procession was from sixty to seventy yards, and yet neither van nor rear was visible. All were moving in one and the same direction, except a few individuals on the outside of the column, which were running rearward, trotting along for a short distance, and then turning again to follow the same course as the main body. But these rearward movements were going on continually from one end to the other of the line, and there was every appearance of this being a means of keeping up a common understanding among all the members of the army, for the retrograding ants stopped very often for a moment to touch one or other of their onward-moving comrades with their antennæ, a proceeding which has been noticed in other ants, and supposed to be their

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