The amphibian landscape

[...] "but they have a body which is of a kind of intermediate nature between all these, of an arid substance, softer than muscle, and in other respects of a nature that may, in strictness, be rather pronounced yielding, than hard. Such, then, is all that they are, and nothing more: in the inside of their bodies there is nothing, except in some few, which have an intestine arranged in folds. Hence it is, that even when cut asunder, they are remarkable for their tenacity of life, and the palpitations which are to be seen in each of their parts." (Pliny, the Elder)