On the natural history and classification of fishes, amphibians, and reptiles / by William Swainson.

  • William Swainson
Date:
1838-1839
Catalogue details

Licence: Public Domain Mark

Credit: On the natural history and classification of fishes, amphibians, and reptiles / by William Swainson. Source: Wellcome Collection.

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    the fishes by these compound animals^ we enter among the batrachians, ox Amphibia; composed of the frogs, toads, sirens, salamanders, efts, and a few other lizard-formed animals, distinguished from all other Vertehrata by the heart having but one auricle, the body naked, and the whole animal undergoing metamorphosis before it reaches maturity. All these are furnished with either two or four feet; but sometimes these members are so small, that they appear more as rudimentary appendages; while, in their eel shaped bodies, they so much resemble many of the apodal fishes, that it may hereafter become a question whether the true passage between the classes is not effected by the eels in one, and the sirens in the other. So closely do the salamanders, again, resemble the lizardsj that none but professed naturalists can tell their difference ; so that the classes Amphibia and Riep- tUia are thus inseparably linked. The connection of the saurian reptiles, or lizards, to the ophidians, or serpents, need not here be insisted upon. The passage from these latter to the gigantic Ichthyosauri is again rendered easy by the Flesiosaurus, where the head and neck of a serpent seems engi’afted, as it were, on the body of an Ichthyosaurus. Lastly, it is quite evident that the fiying lizards, or Pterodactyli, belong to the same great group, and to the same era as the aquatic monsters of a former world just mentioned; and it is equally certain, that of all the reptiles yet discovered, these make the nearest approach to birds : the fore- feet, in fact, were dilated into wings, like those of a
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