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of the ocean would make in their ranks. The manner in which they are propagated has not been ascertained, but from their infinite numbers in every sea, their progeny must be inconceivable.

Another phosphoric animal of the present tribe is distinguished by a dorsal crest, resembling a vesicle full of air, and which it is said to use as a sail, like many of the Molluscans, to conduct it over the surface of the waves. It is connected with the body only by its middle, its extremities being at liberty, which enables the animal to steer its course in any direction.

I shall mention one more of these gelatines, which falls under the observation of every one who is fond of sailing, or rowing, in a boat on the ocean or in its estuaries. If he cast his eye upon the water in fair weather, he will see numbers of animals, in shape resembling an expanded umbrella, with some flesh-coloured organs round the summit or centre, carried with the rising or falling tide, and dancing along with a seemingly undulating motion: these belong to what are vulgarly called the jelly-fish, or sea-nettles.1 Though the body of the animals of this tribe is gelatinous and easily melts, yet its weight is considerable, and it is said that they can render themselves heavy or light at pleasure, which some effect by means of a natatory vesicle, but the means in all has not been ascertained; unless

'PLATE III. FIG. 1.

they were thus gifted, as their specific gravity exceeds that of the water, they could not raise themselves to the surface, where they are seen swimming very gracefully; as it were, by an alternate systole and diastole, admitting and rejecting the sea-water. Several of them,' for it is not common to them all, when touched, cause a sensation similar to that produced by the sting of a nettle: it is supposed by some that this is done by their tentacles, which are conjectured to have little suckers, as indeed is very probable, which adhere to the skin. This faculty, which is supposed to be the lowest degree of the electric power peculiar to several fishes, is found in other genera of this tribe; for instance, the Jamaica sea-nettle,3 is said to affect the hands, when touched, still more severely. Probably this faculty was given to them by Providence, either for the defence of their frail forms against their assailants, or to enable them to secure their prey, this being the general use of their numerous tentacles and other organs. Lamarck observes, that some of these animals are so large as to be more than a foot in diameter, and that some weigh as much as sixty pounds. Their multitudes are prodigious, and, as well as the beroe, they are said to form part of the food of the whale: they are even devoured by some of their own class. The

1 Rhizostoma. Cuv. Cephea Rhizostoma, Lam.

2 See Appendix, note 22.

3 Physalis pelagica.

mode by which these creatures are produced in such infinite profusion is at present unknown. They do not reproduce mutilated parts; therefore it cannot be, as in the polypes, by the division of their bodies.

When we consider the extreme fragility and deliquescent nature of the animals constituting this order of the Radiaries, that a touch almost disorganizes their structure, and moreover that they form part of the food of the most gigantic animals in creation, we should be led to think it impossible that they could withstand all these combined actions upon them, and that however numerous and prolific, they must at length be utterly annihilated. Nothing less, indeed, than Almighty Power, and Infinite Wisdom and prescience, and a Goodness that is interested in the welfare of the meanest as well as the mightiest of the animals he has brought into being, could have preserved them from such a fate. He who made all things decreed their mutual relations, limited their numbers by certain laws, and appointed the means by which those laws should be executed. We may say, that in some sense the whales were created for the gelatinous radiaries and numberless other animals with which the seas frequented by these monsters abound, and that these gelatinous radiaries were created for the whales. The enormous mouth of the lastnamed animals is not armed with tusks or grinders, but fitted instead with vast numbers of

oblique laminæ of a softer substance, usually denominated whalebone, which is adapted only for the crushing and masticating of soft bodies; therefore instead of a prey more proportioned to their bulk, they contentedly make their meal off these small but innumerable gelatines, which, by their number, make up for their want of magnitude, and are exactly suited to the masticating organs of their devourer; and though the waste of animal life seems almost infinite, yet was it not for this check, so great appear to be the powers of multiplication of the smaller creatures that swarm under the ice of the Arctic seas, there would be more than could be maintained consistently with the general welfare.

The object of Providence throughout our globe, as has been before observed, is so to balance the respective numbers of the different kinds of animals, from the invisible monad to the gigantic whale, that a certain proportion may be preserved, with regard to their numbers, between them, so that each may be in sufficient force to accomplish the end for which it was created. We may observe that though the whale devours myriads of millions, yet the quantum of suffering is less than if he were enabled to make his meal off larger animals, and his jaws, like the shark's, were fitted with laniary teeth. In fact the gelatines are incapable of suffering pain, having no digested nervous system, and when

cast upon the shore they dissolve into a fluid exactly resembling sea water.

The Echinoderms1 form the second order of the Radiaries. This name was first given by Bruguières to a class formed solely of Linné's genera Echinus and Asterias, but Lamarck has added others to it. He has divided it into three sections, the Stelleridans, Echinidans, and Fistulidans; in all these the outward envelope is of a much harder substance than in the gelatines, in the first and last of these sections resembling leather, and in the other, consisting of the seaurchins, it is a crust in some degree like that of crabs and lobsters. The animals of this Order, though their nervous system is obscure, have a high degree of muscular motion and are fitted with motive organs.

To look at a star-fish one would wonder, at first, how it could move progressively, its rays seeming not at all calculated for that purpose, this however is wisely provided for. Those of one family send forth a number of tentacles, from a furrow in the underside of the rays into which their body is divided, each terminating in a cup-shaped sucker, which they can lengthen or shorten, and fix to hard bodies. These tentacles, or legs, as Cuvier calls them, are similar

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