第56章
- The Naturalist on the River Amazons
- Henry Walter Bates
- 884字
- 2016-03-02 16:33:10
Swarms of dragonflies appeared in the daytime about the pools of water created by the rain, and ants and termites came forth in the winged state in vast numbers.I noticed that the winged termites, or white ants, which came by hundreds to the lamps at night, when alighting on the table, often jerked off their wings by a voluntary movement.On examination I found that the wings were not shed by the roots, for a small portion of the stumps remained attached to the thorax.The edge of the fracture was in all cases straight, not ruptured; there is, in fact, a natural seam crossing the member towards its root, and at this point the long wing naturally drops or is jerked off when the insect has no further use for it.The white ant is endowed with wings simply for the purpose of flying away from the colony peopled by its wingless companions, to pair with individuals of the same or other colonies, and thus propagate and disseminate its kind.The winged individuals are males and females, while the great bulk of their wingless fraternity are of no sex, but are of two castes, soldiers and workers, which are restricted to the functions of building the nests, nursing, and defending the young brood.The two sexes mate while on the ground, after the wings are shed; and then the married couples, if they escape the numerous enemies which lie in wait for them, proceed to the task of founding new colonies.Ants and white ants have much that is analogous in their modes of life-- they belong, however, to two widely different orders of insects, strongly contrasted in their structure and manner of growth.
I amassed at Caripi a very large collection of beautiful and curious insects, amounting altogether to about twelve hundred species.The number of Coleoptera was remarkable, seeing that this order is so poorly represented near Para.I attributed their abundance to the number of new clearings made in the virgin forest by the native settlers.The felled timber attracts lignivorous insects, and these draw in their train the predaceous species of various families.As a general rule, the species were smaller and much less brilliant in colours than those of Mexico and South Brazil.The species too, although numerous, were not represented by great numbers of individuals; they were also extremely nimble, and therefore much less easy of capture than insects of the same order in temperate climates.The carnivorous beetles at Caripi were, like those of Para, chiefly arboreal.
Most of them exhibited a beautiful contrivance for enabling them to cling to and run over smooth or flexible surfaces, such as leaves.Their tarsi or feet are broad, and furnished beneath with a brush of short stiff hairs; while their claws are toothed in the form of a comb, adapting them for clinging to the smooth edges of leaves, the joint of the foot which precedes the claw being cleft so as to allow free play to the claw in grasping.The common dung-beetles at Caripi, which flew about in the evening like the Geotrupes, the familiar "shard-borne beetle with his drowsy hum" of our English lanes, were of colossal size and beautiful colours.One kind had a long spear-shaped horn projecting from the crown of its head (Phanaeus lancifer).A blow from this fellow, as he came heavily flying along, was never very pleasant.All the tribes of beetles which feed on vegetable substances, fresh or decayed, were very numerous.The most beautiful of these, but not the most common, were the Longicornes; very graceful insects, having slender bodies and long antennae, often ornamented with fringes and tufts of hair.
They were found on flowers, on trunks of trees, or flying about the new clearings.One small species (Coremia hirtipes) has a tuft of hairs on its hind legs, while many of its sister species have a similar ornament on the antennae.It suggests curious reflections when we see an ornament like the feather of a grenadier's cap situated on one part of the body in one species, and in a totally different part in nearly allied ones.I tried in vain to discover the use of these curious brush-like decorations.
On the trunk of a living leguminous tree, Petzell found a number of a very rare and handsome species, the Platysternus hebraeus, which is of a broad shape, coloured ochreous, but spotted and striped with black, so as to resemble a domino.On the felled trunks of trees, swarms of gilded-green Longicornes occurred, of small size (Chrysoprasis), which looked like miniature musk-beetles, and, indeed, are closely allied to those well-known European insects.
At length, on the 12th of February, I left Caripi, my Negro and Indian neighbours bidding me a warm "adios." I had passed a delightful time, notwithstanding the many privations undergone in the way of food.The wet season had now set in; the lowlands and islands would soon become flooded daily at high water, and the difficulty of obtaining fresh provisions would increase.Iintended, therefore, to spend the next three months at Para, in the neighbourhood of which there was still much to be done in the intervals of fine weather, and then start off on another excursion into the interior.