302 NEWTS AND SALAMANDERS. 



originally the permanent condition of all members of the order, and that the 

 salamander stage is a later development. 



There are six other genera, belonging to the subfamily Ambly- 

 Other Genera. . . TT ' 7 . . J y 



stomat^nce, or which Hypnooius is represented by several Japanese 



species. Salawwndrella, distinguished by having only four hind - toes, is a 

 Siberian type, with two species ; Onychodactylus, which may be recognised by its 

 black claws, is known by one species from Japan ; while Ranidens, from Eastern 

 Siberia and North- Eastern China, Batrachyperus from Moupin in Tibet, and the 

 Californian Dicamptodon, all of which have the palatal teeth arranged in two 

 arches, with their convexity forwards, and separated by a wide space in the 

 middle, are likewise respectively represented by a single species. The two 

 remaining subfamilies, which are exclusively American, can receive only very brief 

 notice. In the first of these (Plethodontince) the series of palatal teeth is trans- 

 verse and situated on the hinder part of the vomers ; while there are also teeth on 

 the parasphenoid bone ; the bodies of the vertebrse being cupped at both ends. Of 

 the five genera, Plethodon, with the tongue attached along the middle line to the 

 anterior margin, and five hind-toes, is North American, where it is represented by 

 several species. On the other hand, the large genus Spelerpes, which has the 

 tongue attached only by a central pedicle, and all its edges free, ranges into 

 Central America and the West Indies. The fourth subfamily, Desmognathince, 

 differing from the last by the bodies of the vertebrae being cupped behind and 

 convex in front, is represented only by Desmognathus from North America 

 generally, and Thorius with one Mexican species. 



THE FISH-LIKE SALAMANDERS. 

 Family AMPHIUMID^. 



The members of this family, which, for want of a better name, may be 

 collectively designated by a translation of their German title, fischmolche, differ 

 from the Salamandridce in the absence of eyelids. The bodies of their vertebra 

 are always cupped at both ends. They are all characterised by the weakness 

 of the limbs in comparison to the body, and the wide separation of the front from 

 the hinder pair. They live chiefly or entirely in the water, and breathe by means 

 both of lungs and internal gills in the adult state. Only three genera are known, 

 the first two of which are so closely allied that it is question whether they are 

 really entitled to rank as distinct. 



Giant The earliest record that we have of this family is a skeleton 



Salamander, f rom the upper Miocene of Oeningen in Basle, described by Scheuchzer 

 in the year 1726, under the name of homo diluvii testis; the learned doctor 

 believing that he had to do with a human skeleton, which, like all fossils at that 

 time, was considered to have been buried by the Noachian deluge. This fossil 

 species, which was fully as large as the existing giant salamander, together with a 

 smaller extinct species from lower Miocene strata near Bonn, probably belong to 

 the same genus. The giant salamander (Megalobatrachus maximus) was first dis- 

 covered in 1820 by Siebold in the rivers of Japan, but has been subsequently 



