Ceylon; an Account of the Island Physical, Historical, and Topographical with Notices of Its Natural History - Part 40
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Part 40

_Acalephae_.--Acalephae[1] are plentiful, so much so, indeed, that they occasionally tempt the larger cetacea into the Gulf of Manaar. In the calmer months of the year, when the sea is gla.s.sy, and for hours together undisturbed by a ripple, the minute descriptions are rendered perceptible by their beautiful prismatic tinting. So great is their transparency that they are only to be distinguished from the water by the return of the reflected light that glances from their delicate and polished surfaces. Less frequently they are traced by the faint hues of their tiny peduncles, arms, or tentaculae; and it has been well observed that they often give the seas in which they abound the appearance of being crowded with flakes of half-melted snow. The larger kinds, when undisturbed in their native haunts, attain to considerable size. A faintly blue medusa, nearly a foot across, may be seen in the Gulf of Manaar, where, no doubt, others of still larger growth are to be found.

[Footnote 1: Jellyfish.]

The remaining orders, including the corals, madrepores, and other polypi, have yet to find a naturalist to undertake their investigation, but in all probability the species are not very numerous.

CHAP. VI

INSECTS.

Owing to the combination of heat, moisture, and vegetation, the myriads of insects in Ceylon form one of the characteristic features of the island. In the solitude of the forests there is a perpetual music from their soothing and melodious hum, which frequently swells to a startling sound as the cicada trills his sonorous drum on the sunny bark of some tall tree. At morning the dew hangs in diamond drops on the threads and gossamer which the spiders suspend across every pathway; and above the pool dragon flies, of more than metallic l.u.s.tre, flash in the early sunbeams. The earth teems with countless ants, which emerge from beneath its surface, or make their devious highways to ascend to their nests in the trees. l.u.s.trous beetles, with their golden elytra, bask on the leaves, whilst minuter species dash through the air in circles, which the ear can follow by the booming of their tiny wings. b.u.t.terflies of large size and gorgeous colouring flutter over the endless expanse of flowers, and frequently the extraordinary sight presents itself of flights of these delicate creatures, generally of a white or pale yellow hue, apparently miles in breadth, and of such prodigious extension as to occupy hours, and even days, uninterruptedly in their pa.s.sage--whence coming no one knows; wither going no one can tell.[1] As day declines, the moths issue from their retreats, the crickets add their shrill voices to swell the din; and when darkness descends, the eye is charmed with the millions of emerald lamps lighted up by the fire-flies amidst the surrounding gloom.

[Footnote 1: The b.u.t.terflies I have seen in these wonderful migrations in Ceylon were mostly _Callidryas Hilariae, C. Alcmeone_, and _C.

Pyranthe_, with straggling individuals of the genus _Euploea, E. Coras_, and _E. Prothoe_. Their pa.s.sage took place in April and May, generally in a north-easterly direction.]

No attempt has as yet been made to describe the cla.s.s systematically, much less to enumerate the prodigious number of species which abound in every locality. Occasional observers have, from time to time, contributed notices of particular families to the Scientific a.s.sociations of Europe, but their papers remain undigested, and the time has not yet arrived for the preparation of an Entomology of the island.

What Darwin remarks of the Coleoptera of Brazil is nearly as applicable to the same order of insects in Ceylon: "The number of minute and obscurely coloured beetles is exceedingly great; the cabinets of Europe can as yet, with partial exceptions, boast only of the larger species from tropical climates, and it is sufficient to disturb the composure of an entomologist to look forward to the future dimensions of a catalogue with any pretensions to completeness."[l]

[Footnote 1: _Nat. Journal_, p. 39.]

M. Neitner, a German entomologist, who has spent some years in Ceylon, has recently published, in one of the local periodicals, a series of papers on the Coleoptera of the island, in which every species introduced is stated to be previously undescribed.[1]

[Footnote 1: Republished in the _Ann. Nat. Hist_.]

COLEOPTERA.--_Buprestidoe; Golden Beetles_.--In the morning the herbaceous plants, especially on the eastern side of the island, are studded with these gorgeous beetles whose golden elytra[1] are used to enrich the embroidery of the Indian zenana, whilst the l.u.s.trous joints of the legs are strung on silken threads, and form necklaces and bracelets of singular brilliancy.

[Footnote 1: _Sternocera Chrysis; S. sternicornis_.]

These exquisite colours are not confined to one order, and some of the Elateridae[1] and Lamellicorns exhibit hues of green and blue, that rival the deepest tints of the emerald and sapphire.

[Footnote 1: Of the family of _Elateridae_, one of the finest is a Singhalese species, the _Compsosternus Templetonii_, of an exquisite golden green colour, with blue reflections (described and figured by Mr.

WESTWOOD in his _Cabinet of Oriental Entomology_, pl. 35, f. 1). In the same work is figured another species of large size, also from Ceylon, this is the _Alaus sordidus_.--WESTWOOD, 1. c. pl. 35, f. 9.]

_Scavenger Beetles_.--Scavenger beetles[1] are to be seen wherever the presence of putrescent and offensive matter affords opportunity for the display of their repulsive but most curious instincts; fastening on it with eagerness, severing it into lumps proportionate to their strength, and rolling it along in search of some place sufficiently soft in which to bury it, after having deposited their eggs in the centre. I had frequent opportunities, especially in traversing the sandy jungles in the level plains to the north of the island, of observing the unfailing appearance of these creatures instantly on the dropping of horse dung, or any other substance suitable for their purpose; although not one was visible but a moment before. Their approach through the air is announced by a loud and joyous booming sound, as they dash in rapid circles in search of the desired object, led by their sense of smell, but evidently little a.s.sisted by the eye in shaping their course towards it. In these excursions they exhibit a strength of wing and sustained power of flight, such as is possessed by no other cla.s.s of beetles with which I am acquainted, but which is obviously indispensable for the due performance of the useful functions they discharge.

[Footnote 1: _Ateuchus sacer; Copris sagax; C. capucinus_, &c. &c.]

_The Coco-nut Beetle._--In the luxuriant forests of Ceylon, the extensive family of Longicorns live in destructive abundance. Their ravages are painfully familiar to the coco-nut planters.[1] The larva of one species of large dimensions, _Batocera rubus_[2], called by the Singhalese "_Cooroominya_" makes its way into the stems of the younger trees, and after perforating them in all directions, it forms a coc.o.o.n of the gnawed wood and sawdust, in which it reposes during its sleep as a pupa, till the arrival of the period when it emerges as a perfect beetle. Notwithstanding the repulsive aspect of the large pulpy larvae of these beetles, they are esteemed a luxury by the Malabar coolies, who so far avail themselves of the privilege accorded by the Levitical law, which permitted the Hebrews to eat "the beetle after his kind."[3]

[Footnote 1: There is a paper in the _Journ. of the Asiat. Society of Ceylon_, May, 1845, by Mr. CAPPER, on the ravages perpetrated by these beetles. The writer had recently pa.s.sed through several coco-nut plantations, "varying in extent from 20 to 150 acres, and about two to three years old; and in these he did not discover a single young tree untouched by the cooroominya."--P. 49.]

[Footnote 2: Called also B. _octo-maculatus; Lamia rubus_, Fabr.]

[Footnote 3: Leviticus, xi. 22.]

_Tortoise Beetles_.--There is one family of insects, the members of which cannot fail to strike the traveller by their singular beauty, the _Ca.s.sidiadae_ or tortoise beetles, in which the outer sh.e.l.l overlaps the body, and the limbs are susceptible of being drawn entirely within it.

The rim is frequently of a different tint from the centre, and one species which I have seen is quite startling from the brilliancy of its colouring, which gives it the appearance of a ruby enclosed in a frame of pearl; but this wonderful effect disappears immediately on the death of the insect.[1]

[Footnote 1: One species, the _Ca.s.sida farinosa_, frequent in the jungle which surrounded my official residence at Kandy, is covered profusely with a snow-white powder, arranged in delicate filaments, which it moves without dispersing: but when dead they fall rapidly to dust.]

ORTHOPTERA. _The Soothsayer_.--But the admiration of colours is still less exciting than the astonishment created by the forms in which some of the insect families present themselves, especially the "soothsayers"

(_Mantidae_) and "walking leaves." The latter[1], exhibiting the most cunning of all nature's devices for the preservation of her creatures, are found in the jungle in all varieties of hue, from the pale yellow of an opening bud to the rich green of the full-blown leaf, and the withered tint of decaying foliage. And so perfect is the imitation in structure and articulation, that these amazing insects when at rest are almost indistinguishable from the verdure around them: not the wings alone being modelled to resemble ribbed and fibrous follicles, but every joint of the legs being expanded into a broad plait like a half-opened leaflet.

[Footnote 1: _Phyllium siccifolium._]

It rests on its abdomen, the legs serving to drag it slowly along, and thus the flatness of its att.i.tude serves still further to add to the appearance of a leaf. One of the most marvellous incidents connected with its organisation was exhibited by one which I kept under a gla.s.s shade on my table; it laid a quant.i.ty of eggs, that, in colour and shape, were not to be discerned from _seeds_. They were brown and pentangular, with a short stem, and slightly punctured at the intersections.

[Ill.u.s.tration: EGGS OF THE LEAF INSECT.]

The "soothsayer," on the other hand _(Mantis superst.i.tiosa_ Fab.[1]), little justifies by its propensities the appearance of gentleness, and the att.i.tudes of sanct.i.ty, which have obtained for it its t.i.tle of the praying mantis. Its habits are carnivorous, and degenerate into cannibalism, as it preys on the weaker individuals of its own species.

Two which I enclosed in a box were both found dead a few hours after, literally severed limb from limb in their encounter. The formation of the foreleg enables the tibia to be so closed on the sharp edge of the thigh as to amputate any slender substance grasped within it.

[Footnote 1: _M. aridifolia_ and _M. extensicollis_, as well as _Empusa gongyloides_, remarkable for the long leaf-like head, and dilatations on the posterior thighs, are common in the island.]

_The Stick-insect_--The _Phasmidoe_ or spectres, another cla.s.s of orthoptera, present as close a resemblance to small branches or leafless twigs as their congeners do to green leaves. The wing-covers, where they exist, instead of being expanded, are applied so closely to the body as to detract nothing from its rounded form, and hence the name which they have acquired of "_walking-sticks_." Like the _Phyllium_, the _Phasma_ lives exclusively on vegetables, and some attain the length of several inches.

Of all the other tribes of the _Orthoptera_ Ceylon possesses many representatives; in swarms of c.o.c.kroaches, gra.s.shoppers, locusts, and crickets.

NEUROPTERA. _Dragon-flies._--Of the _Neuroptera_, some of the dragon-flies are pre-eminently beautiful; one species, with rich brown-coloured spots upon its gauzy wings, is to be seen near every pool.[1] Another[2], which dances above the mountain streams in Oovah, and amongst the hills descending towards Kandy, gleams in the sun as if each of its green enamelled wings had been sliced from an emerald.[3]

[Footnote 1: _Libellula pulch.e.l.la._]

[Footnote 2: _Euphoea splendens_, Hagen.]

[Footnote 3: _Gymnacantha subinterrupta_, Ramb. distinguished by its large size, is plentiful about the mountain streamlets.]

_The Ant-lion_.--Of the ant-lion, whose larvae have earned a bad renown from their predaceous ingenuity, Ceylon has, at least, four species, which seem peculiar to the island.[1] This singular creature, preparatory to its pupal transformation, contrives to excavate a conical pitfall in the dust to the depth of about an inch, in the bottom of which it conceals itself, exposing only its open mandibles above the surface; and here every ant and soft-bodied insect which, curiosity tempts to descend, or accident may precipitate into the trap, is ruthlessly seized and devoured by its ambushed inhabitant.

[Footnote 1: _Palpares contrarius_, Walker; _Myrmeleon gravis_, Walker; _M. dirus_, Walker; _M. barbarus_, Walker.]

_The White Ant_--But of the insects of this order the most noted are the _white ants_ or termites (which are ants only by a misnomer). They are, unfortunately, at once ubiquitous and innumerable in every spot where the climate is not too chilly, or the soil too sandy, for them to construct their domed edifices.

These they raise from a considerable depth under ground, excavating the clay with their mandibles, and moistening it with tenacious saliva[1]

until it a.s.sume the appearance, and almost the consistency, of sandstone. So delicate is the trituration to which they subject this material, that the goldsmiths of Ceylon employ the powdered clay of the ant hills in preference to all other substances in the preparation of crucibles and moulds for their finer castings; and KNOX says, in his time, "the people used this clay to make their earthen G.o.ds of, it is so pure and fine."[2] These structures the termites erect with such perseverance and durability that they frequently rise to the height of ten or twelve feet from the ground, with a corresponding diameter. They are so firm in their texture that the weight of a horse makes no apparent indentation on their solidity; and even the intense rains of the monsoon, which no cement or mortar can long resist, fail to penetrate the surface or substance of an ant hill.[3]

[Footnote 1: It becomes an interesting question whence the termites derive the large supplies of moisture with which they not only temper the clay for the construction of their long covered-ways above ground, but for keeping their pa.s.sages uniformly damp and cool below the surface. Yet their habits in this particular are unvarying, in the seasons of droughts as well as after rain; in the driest and least promising positions, in situations inaccessible to drainage from above, and cut off by rocks and impervious strata from springs from below. Dr.

Livingstone, struck with this phenomenon in Southern Africa, asks: "Can the white ants possess the power of combining the oxygen and hydrogen of their vegetable food by vital force so as to form water?"--_Travels_, p.

22. And he describes at Angola an insect (A. goudotti? Bennett.) resembling the _Aphrophora spumaria_; seven or eight individuals of which distil several pints of water every night.--P. 414. It is highly probable that the termites are endowed with some such faculty: nor is it more remarkable that an insect should combine the gases of its food to produce water, than that a fish should decompose water in order to provide itself with gas. FOURCROIX found the contents of the air-bladder in a carp to be pure nitrogen.--_Yarrell_, vol. i. p. 42. And the aquatic larva of the dragon-fly extracts air for its respiration from the water in which it is submerged. A similar mystery pervades the inquiry whence plants under peculiar circ.u.mstances derive the water essential to vegetation.]

[Footnote 2: KNOX'S _Ceylon_, Part I, ch. vi. p. 24.]

[Footnote 3: Dr. HOOKER, in his _Himalayan Journal_ (vol. i. p. 20) is of opinion that the nests of the termites are not independent structures, but that their nucleus is "the debris of clumps of bamboos or the trunks of large trees which these insects have destroyed." He supposes that the dead tree falls leaving the stump coated with sand, _which the action of the weather soon fashions info a cone_. But independently of the fact that the "action of the weather" produces little or no effect on the closely cemented clay of the white ants'

nest, they may be daily seen constructing their edifices in the very form of a cone, which they ever after retain. Besides which, they appear in the midst of terraces and fields where no trees are to be seen; and Dr. Hooker seems to overlook the fact that the termites rarely attack a living tree; and although their nests may be built against one, it continues to flourish not the less for their presence.]

In their earlier stages the termites proceed with such energetic rapidity, that I have seen a pinnacle of moist clay, six inches in height and twice as large in diameter, constructed underneath a table between sitting down to dinner and the removal of the cloth.