SUB-CLASS II. AMPHIBIA.
(Naked Reptiles.)
So important are the differences between the animals we have been considering, and those at which we are now arrived, that some zoologists of the greatest eminence consider them as forming two distinct Classes, or groups equal in rank to the Mammalia, Birds, and Fishes; though others of high reputation prefer to give to the latter no higher rank than that of an Order of the Class Reptilia, thus making this group only equal in value to the Testudinata, or Sauria respectively. It is principally for the convenience of describing both in a single volume, that we assign to the Amphibia an intermediate place; making them a group of equal rank to the rest of the Reptilia put together, but not one of the primary divisions of the Vertebrata.
The Amphibia, though widely distributed, are not very numerous, nor do any of them attain a large size. Destitute for the most part of the attractions of form and colouring, they are not generally considered interesting, except to the philosophical observer of the works of God; but he, however, perceives in them abundant evidences of creative wisdom.
The most obvious character of these animals is that of their integuments. The skin is naked, not being defended by plates or scales, or any