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Analogies between Plants and Animals.
for their impregnation ; since the pollen of the male is waftell to the stigmatas on the wings, the thorax, the abdomen, the proboscis, or the antennæ of those fies, wasps, and bees, that rob them of their nectar.
But some plants, even of the most general classes, produce seeds without receiving pollen from the male. Hens, in the same manner, lay eggs without being visited by the cock: but seeds, thus formed, will never fructify; nor will eggs, thus laid, produce living animals. Some plants, too, grow upon other plants. The misseltoe rises out of the oak and the apple; and the mountain ash frequently springs from a berry, deposited by a bird in the chink of a yew-tree. The American loranthus climbs the coccoloba' grandiflora, and other high trees, in Jamaica, Hayti, Martinico, and Barbadoes; and its roots, like ivy, fixing firmly to their bark, like other parasitical plants, they borrow nourishment from the trees to which they cling. There is a mushroom which grows on the upper extremities of the white pines of Canada ; and in the forest of Geltsdalo, the Earl of Carlisle has an ash, an alder, and a mountain ash growing out of the same solid trunk. Here, too, we may mark some resemblance with the manners of birds and insects. The cuckoo lays its eggs in the nest of a hedge-sparrow; the long-eared owl lays its eggs in the old nest of a magpie; and the hornet-fly deposits hers in the cells of an humblebee. Some birds, as the American goat-sucker, make no nest at all; but drop their eggs, as many fishes shed
their spawn, careless what becomes of them. Birds, however, are for the most part assiduous in their paternal duties. Some plants bear analogies even with these : the tamarind closes upon its fruit, when the sun has set, in order to preserve it from the dew; and in Ceylon and in Java grows a plant' remarkable for having a small vegetable bag attached to the base of its leaves. This bag is covered with a lid, which moves on a strong fibre, answering the purpose of a hinge. When dews rise, or rains descend, this lid opens; when the bag is saturated, the lid falls, and closes so tightly that no evaporation can take place. The moisture, thus imbibed, cherishes the seed, and is gradually absorbed into the body of the plant. Sharks permit their young ones to retreat, in times of danger, into their stomachs; and there are some land animals, also, that possess the power of resisting the action of the gastric juice.
Some flowers are even viviparous; but I know of none that bear even a distant relation to the toad ; which impregnates the eggs of the female as they issue from her anus. The potatoe, on the other hand, claims a peculiarity,on behalf of vegetables, not unworthy of observation. It produces more abundantly from a small portion of its fruit, than from the seed itself. There is nothing in animals associating with this. Some plants, too, have not even so much as a root. The fucus natans and the conferva vagabundi swim on the surface of the sea like a nautilus. They may, therefore, not inaptly be styled plants of
1 The Nepenthes distillatoria. Voy. Cochin-China, 189, 4to.
passage. The former swims upon the grassy sea; and the latter among the estuaries of Carnarvon and Merioneth, and not unfrequently in Milford Haven. Some plants may, also, be propagated by being engrafted or inoculated. Thus by inoculating one tree with the buds of others, several fruits may be made to grow upon one tree. Engrafting is performed either by insinuating a bud or scion into the stock, into the rind, into the bark, between the rind and the bark, or into the root itself.
In general economy, the internal structure of viviparous and oviparous animals are different; but in serpents the conformation of both is the same. In the leech there seems to be no passage, by which it can eject the blood it has taken into its body. It will remain clotted, but not putrified, for months ; and little altered either in texture or consistence. It probably exudes by medium of the pores. Insects have no bones :-their blood is not red :-their mouths open lengthwise :- they have no eyelids :--and their lungs open at their sides. They seem to have the capacity of hearing, but they have no ears. Lizards exhibit remarkable phenomena. They are neither beast, fish, bird, serpent, nor insect; and yet, in some measure, they share the natures of them all. Some are viviparous, like beasts, as the Lophius piscatorius; others oviparous, like birds : some shed spawn like fishes; some have teeth like serpents; and others none,
insects. Some plants bear fruit on the backs of their leaves ; as spleenwort, maiden hair, fern, brake, pepper
grass, and many species of moss. After the same manner, the Lapland marmot, the spider, and the American scorpion, carry their young upon their backs, wherever they go, in case of alarm. The monoculus insect carries its young on its back even in the water ; but the Surinam toad exhibits a still more wonderful phenomenon :-its eggs are buried in the skin of its back. When the animals, enclosed in those eggs, burst from their shells, the mother is seen crawling, with her family riding on her person; some still in the egg; others just emerging out of it; and some clinging to various parts of her body.
Affinities of electricity may be traced in marine substances, in insects, vegetable oils, and mineral essences. In 42° 30 south of the Line' are seen a multitude of minute sea animals, emitting colours equal to those of the most brilliant sapphires and rubies. When observed by candle-light, they appear of a pale green. In the Gulf of Guinea, ships seem frequently to sail, at night, in a sea of milk”; a whiteness, which is occasioned by pellucid salpæ, and crustaceous animals of the scyllarus genus, attached to them. Other oceans contain a particular species of sea anemones, so brilliant, that the terms white, carmine, and ultra-marine, are3 insufficient to ex14 Fire-flies of the Torrid Zone. press their beauty. In the River St. Lawrence', luminous appearances are caused by a vast number of porpoises darting and crossing each other with great velocity. Star fishes, also, float on the surface of the sea in summer, and emit light like phosphorus. By land these luminous appearances are far from being unknown; though in instances more detached. :: When Misson’ was in Italy, he observed the hedges, bushes, fields, and trees, covered with innumerable fiés (lucicole), which gave great splendour to the evening air.' The fulgoria candelaria, and the diadema, give equal brilliancy to many parts of China and India. In the Torrid Zone, also, countless multitudes of phosphorescent insectså fly in all directions, and give light to groves of palms and mimosas. The elata noctilucus of South America emits a light so brilliant, that ten of them are equal to the effulgence of a candle: while the Peruvian fulgoria, having a head nearly as large as its entire body, is so luminous, that four, tied to the branch of a tree, are carried, near Surinam, to guide travellers by night. Light is emitted, also, by dead plants, and rotten carcasses : while sulphuric acid, if mixed with water, emits a heat more violent than even boiling water.
2 Tuckey, p. 48, 4to. 3 Abbé Dieguemarre, Phil, Trans. for 1773, art. 37,