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them to be sustained in the atmosphere to a great distance. The roridula dentata has leaves covered with fine hairs, and a glutinous substance, to which small insects adhere; and their eggs are, in consequence, wafted to wherever that plant is

carried.

Some animals are wafted by the drifting of canoes. In desert islands, where there are no quadrupeds but rats, fragments of canoes have been observed, stranded on the shores. Those canoes were probably the media, by which those animals were conveyed. Many vegetables of the Friendly and Society adorn the Sandwich Islands; though many leagues distant. Islands, situate from the 50th to the 55th degree of latitude, have the same beasts, birds, fishes, and shells, that are found upon the Kurili Islands: and those, from the 55th to the 60th degree of latitude, have many animals that are found on the peninsula of Kamschatka.

Bears, foxes, ermines, seals, and walruses; wild fowl; the spawn of river-fish, and the eggs of northern birds, are carried to distant longitudes and latitudes by ice islands. Of these islands there are two species;-one composed of sea water; the other of fresh water. The former kinds are white, and have little transparency: the latter blue, and so clear, that objects may be seen to a considerable depth. These are mostly formed on the sides of rocks, jutting over seas or large rivers. They melt in summer, at the lower extremities, by the influence of the sun, and the moisture of the waves below. Thus undermined, their bulk becomes too ponderous for their base they break; and, falling into the river or sea, float and being joined by others, unite and form themselves into islands of vast length, breadth and height: And not unfrequently sail with the winds, currents, and tides, from the arctic circle to the utmost extremity of the temperate zone;exhibiting, as they sail along, upon a minute survey, innumerable combinations-occasioned by the spray of the sea,

a Vide Stæhlius' Account of the New Northern Archipelago, p. 18.

t;

the mists, and the snows,-of trees, and flowers; villages, towns, and cities; ruins, and palaces; and myriads of forms before unknown, even to the imagination.

The mountains of ice, which are composed of fresh water, are not unfrequently incorporated with soil, stones, and brushwood; and covered with the eggs of those birds, which frequent the coasts, from which they fall. The salt water islands bear sea weeds, spawn, and not unfrequently bears, foxes, and ermines. In the north of Iceland b, the cold splits the calcined mountains, from which large masses fall in detached pieces, and roll precipitately into the sea, like waterfalls.

The approach of ice islands is indicated by the bluish lustre, which appears in the horizon. They are often covered, too, with an immense number of seals and sea calves; which are seen rolling and sporting in the snow, and seem by no means terrified at the approach of either men or ships: reminding the voyager of those lines of Cowper, which he puts into the mouth of Alexander Selkirk,

The beasts, that roam over the plain,

My form with indifference see:
They are so unacquainted with man,
Their tameness is shocking to me.

Professor Smith saw several islands, floating from the African rivers, which, upon inspection, he found to bear reeds, resembling the donax, a species of agrostis, and some branches of justicia, with the roots of mangrove and papyrus. There were, also, in the midst of them, several small animals; which are found, also, floating on the Grassy Sea “.

Reptiles are probably propagated to distant regions by their eggs, or embryos, being casually dropt on the sea shore, at low ebb, and borne away by the returning tides. Some

a In one of the Dutch voyages to Nova Zembla, the captain ascended an iceberg, on the top of which were a considerable quantity of earth, and forty birds' eggs. b Freminville, Voyage to the North Pole, p. 12. Journal-Tuckey, p. 259.

Scyllæa Pelagica.—Cancer minutus.-Lophius histrio, &c. &c.

insects are transported on the backs, and in the intestines of animals others in their skins. The hair-worm lives not only in the earth, on the leaves of trees, and in the water, but in the bodies of beetles: while large flies enter the ears of elks, in the Lapland forests; and take up their winter quarters in their heads.

Vipers are easy of transportation; since they possess such a faculty of abstinence, that some species will remain even six months without food. Canadian bears, also, frequently live without sustenance so long, that many persons believe, they can live by licking their own paws.

It is exceedingly curious, that in Ireland there is neither a mole, a spider, nor any venomous reptile or insect. Frogs, a hundred years ago, were foreign to Ireland; but having been observed, for the first time, in a well at Moira, in the county of Down, they have multiplied all over the island. How came they into that well? There are no frogs in Lapland"; nor, I believe, in Iceland; but in 1783, the pastures of that island abounded in small insects, which had never been seen there before. They resembled, in some degree, the earthfly; blue, red, yellow, and brown. The weevil, in the same manner, will not live in Van Diemen's Land: in which island grows the cedar (huon pine), which has the property of repelling insects. The cochineal has been found extremely difficult to transplant: and it is remarkable, that though insects are the most liable to corruption of all animals, the cochineal never spoils. It has, therefore, been preserved for ages.

The spawn of some fishes are propagated by insects and aquatic birds: some of which even void the fishes, they have gorged, without any change in the fishes themselves.

b Hooker, ii. 5.

Eels

Lachesis Lapponica, i. 177. The large water-beetle feeds on spawn. It rises on the leaves of the water-plants, and takes wing. By this insect mountain lakes are frequently stocked.

are thus transported". Cranes swallow them alive; and void them alive; and thus fish-ponds are frequently stocked in a manner very mysterious to their proprietors.

Ponds are often stocked with fish too by wild ducks, which, in their emigrations, carry impregnated spawn a.

The ostrich will eat wood, stones, glass, and pieces of iron ; and void them whole. The polypus frequently swallows a polypus; which afterwards issues from its body, perfect and uninjured. The ocythoe polypus takes up its residence in the shell of a nautilus; and in this manner is conveyed from one coast to another.

a The eel is seldom seen in the Danube; a very remarkable circumstance, since it is migratory, especially in tempestuous weather. Sir Everard Home says, he is firmly convinced that the eel is hermaphrodite, and impregnates itself. See Davy's Life, p. 455, 4to.

b This is not more extraordinary than that worms should be capable of living not only in the intestines of the human body, but in those of quadrupeds, birds *, seals †, and fishes. The Acarus aquaticus deposits its eggs in the water-scorpion; and the Pulex penetrans of South America inserts its eggs under the toe-nails of men and monkeys. The teeth of Laplanders ‡ are corroded by worms; and a woman of Sweden § once bred a quantity of flies in her nose.

c Colonel Sykes states, that in the ponds in the East Indies, which have become perfectly dry and the mud hard, the next rainy season will find them full of fish, although wholly unconnected with any stream or passage by which they can be connected. Mr. Yarrell, in his History of British Fishes, says, The solution appears to me to be this: the impregnated ova of the fish of one rainy season are left unhatched in the mud through the dry season, and from this low state of organization as ova the vitality is preserved, the occurrence and contact of the rain and the oxygen of the next season, when vivification takes place through their joint influence. If this solution of the problem be the true one, it points at once to what may be effected after a few experiments -namely, the artificial fecundation of the roe, the drying of that roe (or of other roe naturally impregnated) sufficiently to prevent decomposition, and its possible transportation to, and vivification in, distant countries.—Anon.

d In most instances, fishes lay the unimpregnated eggs; the male coming afterwards, and sprinkling them with his semen.-Vid. Blumenbach's Elem. Nat. Hist. 148.

* Grouse are troubled with the tape-worm. + Genus Eschinorhycnus.-Freminville, p. 6. § Memoirs of the Swedish Academy.

Acerbi, ii. p 290, 4to.

If some plants have riveted partialities to peculiar soils, some insects have equal partialities to particular plants. The cochineal is wedded, as it were, to the fig-tree; the aphis to beans, peas, and rose-trees; the musk-beetle to willows; the papilio machaon to fennel; the phalana grossulatriata to currant bushes; the phinx licustri to poplar, privet, and lilac leaves; and the sphinx atropos to jessamine and love-apple. There is a small red insect, too, which seems to be almost entirely devoted to the violet; and these emigrate with the plants, to which they are attached.

The tenthredo insects proceed from the galls of willow, beech, holly, hairy hawkweed, and ground ivy: while the leptura of Finland lies concealed in the corolla of the globeflower. The caterpillar, which changes to the phalana tortix, and the hawkmoth, emigrate with the woodbine. The former curls itself up in its leaves; and the latter hovers over its blossoms of an evening, and extracts honey from the bottom of its nectarium.

Most shrubs and trees have particular species of the aphis attached to them: all varying in size, structure, and manners; and were we to enumerate the whole, we should enumerate almost every species of tree and shrub now in existence.

Some insects emigrate with the atmosphere: for the atmosphere is not only a temporary receptacle for many small aquatic and terrestrial seeds; but for the eggs of insects, and imperceptible animalcules, which, having surfaces resembling feathers, are easily wafted. Saussure saw two butterflies on Mont Blanc; and a lady-bird once flew against my face on the circular balustrade of St. Paul's cathedral.

Many insects, and even birds, are doubtless carried through the air by trade winds. Others float upon the ocean; are picked up by marine birds; and afterwards discharged, entire, on the islands upon which they rest: as some birds do fish. It is curious here to remark, that the heat and strength of

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