That the Proteus from Germany, as well as that from Carolina, is an animal in its perfect state, I consider to have been proved by Baron Cuvier, in his account of the skeletons of these animals; and when I found that their vertebræ were cupped, which is not the case in the Aquatic Salamander, to which in many respects they are nearly allied, that circumstance alone, with me, distinguished them from all the lizard tribe. Having had the opportunity of examining the vertebræ of the Proteus from Mexico, and finding them also cupped, I could have no doubt of its belonging to the same tribe, and consequently an animal in it's perfect state. This, however, required proofs, that could only be afforded by an examination of the organs of generation in a developed state.