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rities, which are now, for the first time, presented to the British Public. These are "the true P. vitulina" of the French Coast, (No. 3,) and the MarbledSeal, (No. 4,) of the distinguished Cuviers; the Rough-Seal, (No. 8,) one of those animals which constitutes a considerable portion of the Northern Seal fishery; the Hare-Seal of Northern Russia, (No. 9;) the Small-nailed Seal of De Blainville, (No. 11;) the Crested-Seal, (No. 14,) and the Hooded-Seal, (No. 15,) over both of which there still hangs considerable obscurity; the Sea-Elephant of Peron, (No. 16,) the chief object of the South Sea fishing for Seal oil; and the Cape, (No. 20,) and Lesson's Otaries, (No. 24.) These exhibitions of fifteen species, (may we call them?) obtained from sources and authorities of established celebrity, together with those more familiarly known, and our best efforts to associate with each whatever specific information has been collected, will do something, we trust, to increase the facilities of investigation, as well as provoke the further endeavours of Naturalists, and others, to new triumphs over the many difficulties which still envelope this interesting subject.

THE AMPHIBIOUS CARNIVORA.

AN Amphibious animal is said to be one which is able to live in two elements, the elements implied being air and water; and there was a time when it was generally supposed that there were such quadrupeds in existence. The reader will please to observe, that we are not here speaking of animals which can reside on the land, and in and on the water; for such there unquestionably are; on these we are about to dwell, and in this old and familiar acceptation of the term we mean to use it.* But the time

For this we can quote nearly universal usage, in the present and preceding ages, and some of the most authoritative names in the science; amongst others those of Baron Cuvier and Latreille. It is true that Cuvier did not here follow the footsteps of Linnæus, who placed these Amphibia in his 2d and 3d order, Bruta and Fera, and made the Amphibia his 3d class, including Tortoises, Frogs, Serpents, and many true Fish, such as the Sturgeon, Shark, Skate, &c., so making a great jumble. We may add,

is not long gone by when it was supposed that these Amphibia differed from all other animals, in that it was to them a matter of indifference whether they lived on land, and breathed the common air of heaven, or resorted to the water, and there carried on the process corresponding to that of respiration, as do the fishes in the sea. It is generally known that both in quadrupeds and fishes there is a kind of double circulation of the blood, the greater, moving round the whole body, for the purpose of its growth and regular nourishment, and the lesser, confined to the lungs or the gilis, having for its object the purification of the blood, that it may be fitted for its proper uses. It was very evident that, when living in the water, these Amphibia could no more use their lungs than man could do, and it was equally well known that they had no gills, by which they could live as fish do; and the question therefore occurred, By what peculiar arrangement is it that these animals live in water without gills and without air? Nor was it long before an explanation of the phenomenon was offered. The two circulations above alluded to do not communicate with each other, generally, throughout their circuit; but

that previous to Linnæus' death, a single animal was discovered which could live not only on land but also in water. This was the Lizard Siren of Carolina, which is possessed of true lungs and true branchiæ, and can use them severally on land and in water. Since that date a few other animals have been discovered similarly constituted; and this has led Naturalists to arrange them in a separate class or subdivision.

in the Amphibia it was held that a sluice-gate existed between the two, which was opened when they were under water, so that no obstruction occurred to the circulation. By this aperture, (which existed in the heart, and was called the oval hole, foramen ovale,) it was asserted that both circulations went forward, and without any prejudice to life. It is because this statement still maintains its ground in some of our most popular works on natural history that we have thought it right to notice it. Thus the eloquent Buffon," The Seals and Walrus alone can live equally in air and in water, and consequently they alone merit the appellation of Amphibious." And no wonder the Count made this statement, because he only quoted the memoirs of the most learned societies of the day,-" As these animals remain long in the water, and thus the transmission of the blood cannot be performed without respiration, they have the foramen ovale open, and therefore do not require to respire."* In these sentiments he in fact only re-echoed the opinions of the Physiologists of his time.†

The hypothesis was in fact based on erroneous statements, which passed current for facts. It is true these Amphibious animals live long in the water, but still they must regularly come to the surface, and they breathe precisely after the manner of

Hist. de l'Acad. des Sciences, tom. i. p. 84.

+ Though this explanation is sufficieut apology for Buffon, yet the same theory, founded on the same errors, should not have appeared in Bingley's British Quadrupeds, 1829.

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