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phia, besides some Polythalmia and Spongolites. The following are American forms :Arcella constricta,
Eunotia quarternaria, Desmogonium Guayanense,
quinaria, Eunotia Camelus,
Stauroneis dilatata, Synedra Entomon,
Fragmenta incerta. A simultaneous occurrence of dust showers and falls of meteoric stones, has been observed in probably eighteen instances before the Christian era. During the Christian era, fourteen coincidences have been observed, making thirtytwo in all.
(Tables and Drawings of Infusoria in a future Number.)
Singing Birds and Sweet Flowers in Jamaica. “ In tropical countries, where brilliant and varied colours have been granted to the birds and flowers, song has been denied to the one and fragrance to the other.” This is one of those flippant generalisations which people are fond of repeating, originally made without investigation, and perpetuated without inquiry. In Jamaica it is certainly very far from truth ; and I suspect would be found as groundless everywhere else. The groves and fields of this sunny isle ring with the melody of birds, to a degree fully equal, in my judgment, to that of Europe. In the lone forests of the mountain heights the Glass-eye Merle (Merula Jamaicensis) pours forth a rich and continued song; and that mysterious harmonist, the Solitaire (Ptilogonys armillatus), utters his sweet but solemn thrills, long-drawn and slow, like broken notes of a psalm, so perfectly in keeping with the deep solitude. In the woods that cover, as with an ever verdant crown, the lower hills, the Black Shrike (Tityra leuconotus), and the Cotton-tree Sparrow (Pyrrhula violacea), enunciate their clear musical calls, so much alike as scarcely to be distinguished; four or five notes running up the scale so rapidly, as to be fused as it were together, and suddenly falling at the end. There, too, sits the Hopping Dick (Merula leucogenys), and whistles, by the hour together, a rich and mellow
succession of wild notes, clear and flute-like, like his European cousin, the Blackbird. The constantly reiterated call of the Red-eyed Flycatcher (Vireosylva olivacea), “ John to whip! John to whip!" heard at different distances from all parts of the woods, makes their green glades lively; and the loud varied voice of the White-eyed Flycatcher Vireo Noveboracensis), sometimes soft and subdued, sometimes shrill and piercing, is always heard with pleasure.
But birds are particularly social animals : and it is chiefly in the neighbourhood of the presence of man that their melodious voices are heard, as if to cheer him in his toil; the fields, and pastures, and meadows, the hedges, and hedgerow trees, that border and map out his domains; the orchards and groves that surround and embosom his dwellings, affording grateful fruit and shadow from the heat :--these are the situations in every inhabited country that most resound with the voices of feathered songsters. The beautiful park-like estates of the southern slopes of Jamaica, present scenes peculiarly inviting and suitable for the winged orchestra to exercise its vocal talent; and the notes of melodious joy are pouring forth in them from earliest dawn to sunset; aye, long before dawn, and long after the veil of night has been outspread. The swallows (Hirundo paciloma) that shoot along in their arrowy traverses over the plains, now darting across the placid stream, now coursing far up in the thin air, almost lost in the glaring sun-beam, twitter sweetly as they pass, and now and then one and another sitting on the summit of a low tree, commence a stammering song by no means deficient in music. The Blue Martins (Progne Dominicensis), too, sit side by side in close rows on the dead frond of some tall palm, or on the roof-ridge of the dwelling house and utter a shrill but not unmelodious chant.
From the green tussocks of the Guinea-grass fields comes the singular hollow cry of the Tichicro (Coturniculus tixicrus), and now and again he runs to the summit of a stone, or jumps upon a wall, and warbles a sweet low song. The clear whistle of the Banana bird (Icterus leucopteryx) like the tones of a clarionet, resound from the fruit trees, among whose deep green foliage his gay hues, rich yellow, white, and black, glance fitfully as he shoots to and fro; and his companions, the little Blue
Quits (Euphonia Jamaica), equally devoted admirers of a ripe sour sop or custard-apple, accompany his loud notes with strains of their own, full of soft warbling music. And the most minute of birds, the tiny Vervain Humming bird (Mellisuga humilis), not larger than a school-boy's thumb, utters a song so sweet, but of sound so alternated withal, that you wonder who the musician can be, and are ready to think it the voice of an invisible fairy ; when presently you see the atom of a performer perched on the very topmost twig of a mango or orange tree, his slender beak open and his spangled throat quivering, as if he would expire his little soul in the effort.—P. U. Gosse, Jamaica.
(To be continued in our next Number.)
I. Coral Reefs and Islands. II. The Structure, Growth,
. , and Habits of Coral Zoophytes. By JAMES D. DANA, Esq., Naturalist to the American Exploratory Expedition.
1. General Features of Coral Reefs and Islands. The general features of reefs and coral islands have often been delineated by travellers, and are probably almost as familiar to the reader as the scenes of the land around us. Yet a few brief remarks on this subject will not be out of place here as preliminary to our observations on the structure, growth, and habits of coral zoophytes.
Coral Reefs.-A wide platform of rock covered with the sea, except at low tide, borders most of the high islands of the Pacific. It is a vast accumulation of coral, based upon the bottom in the shallow waters of the shores. This bank or table of coral rock, is of varying width, from a few hundred feet to a mile or more ; and, although the surface is usually nearly flat, it is often intersected by irregular boat-channels, or occasionally encloses large bays, affording harbour protection to scores of ships. In very many instances the reef stands at a distance from the shores like an artificial mole, leaving a wide and deep channel between it and the land ; and within this channel are other coral reefs, some in scattered patches, and others attacbed to the shore. The inner reef in these cases, is distinguished as the fringing reef, and the outer as the barrier reef. The sea rolls in heavy surges against the outer margin of the barrier; but the still waters
VOL. LII. NO. CIII.--JANUARY 1852.
of a lake prevail within, affording safe navigation for the tottling canoe sometimes through the whole circuit of an island ; and not unfrequently, ships may pass, as by an internal canal, from harbour to harbour around the island. The reef is covered by the sea at high tide, yet the smoother waters indicate its extent, and a line of breakers its outline. Occasionally a green island rises from the reef, and in some instances a grove of palms stretches along the barrier for miles, where the action of the sea has raised the coral structure above the waves.
The sketch annexed conveys some idea of the peculiar features presented by a Pacific island, and its encircling reefs, though in order to fill out the scene, the jagged heights and deep gorges of the islands should be covered with forests, and the shores with groves and native villages. The coral platform which borders the shore is represented with its usual uneven line,——its broad harbours with a narrow entrance,—and to the left, an irregular ship-channel running between the inner or fringing reef, and the outer or barrier. At a single place the sea is faced by a cliff, and here, owing to the boldness of the shores and the depth of the waters, the reef is wanting. To the right there is only a fringing reef.
Coral Islands.—Coral islands resemble the reefs just described, except that a lake or lagoon is encircled instead of a mountainous island. A narrow rim of coral reef, generally but a few hundred yards wide, stretches around the enclosed waters.
In some parts it is so low that the waves are still dashing over it into the lagoon; and in others, it is still verdant with the rich foliage of the tropics. The coral-made land, when
highest, is seldom elevated over eight or ten feet above high tide.
When first seen from the deck of a vessel, only a series of dark points is descried just above the horizon. Shortly after, the points enlarge into the plumed tops of cocoa-nut trees, and a line of green, interrupted at intervals, is traced along the water's surface. Approaching still nearer, the lake and its belt of verdure are spread out before the eye, and a scene of more interest can scarcely be imagined. The surf beating loud and heavy along the margin of the reef, presents a strange contrast to the prospect beyond,—the white coral beach, the massy foliage of the grove, and the embosomed lake with its tiny islets. The colour of the lagoon water is often as blue as the ocean, although but fifteen or twenty fathoms deep; yet shades of green and yellow are intermingled, where patches of sand or coral knolls are near the surface; and the green is a delicate apple-shade, quite unlike the usual muddy tint of shallow waters.
The belt of verdure, though sometimes continuous around the lagoon, is usually broken in some parts into islets, which are separated by varying intervals of bare reef; and through one or more of these intervals a ship-channel occasionally opens into the lagoon. The larger coral islands are thus a string of islands arranged along a line of coral reef. The King of the Maldives bears the high sounding title of “Ibrahim Sultan, King of the thirteen Atollons and Twelve Thousand Isles ;" which Captain W. F. W. Owen, R.N., remarks is no exaggeration.
The usual features of these islands are presented in the above sketch. The narrow belt is seen to consist of several patches of vegetation, and within are the quiet waters which offer a retreat for vessels whenever there is an opening to the lagoon.
A few small coral islands are simple reefs without lagoons. In some cases they are bare banks of coral ; but generally, the usual vegetation of the islands has obtained a foothold, and afford some protection against the glare of the coral sand.*
* For further observations on Coral Reefs and Islands vide Dana's Memoir in Silliman's Journal, May 1851.