American Amphibia. 321 
class, by which the ordinal character of M. Brongn. is invalida- 
ted,) thus Rana and Hyla are distinguished from Bufo, by the 
presence of teeth in the upper jaw, and in two transverse processes 
of the palate, generally anterior to the internal nares, sometimes’ 
between, but never behind them, the toads being quite destitute 
of both. The Salamandrae possess not only teeth in both jaws, 
but also palatines, which according to most authors, are arranged 
in two longitudinal rows. This character does not agree with 
my observations upon our Salamandrae. Indeed so varied is the 
arrangement of the palatine teeth in those American Salamanders 
which have fallen under my observation, that if much importance 
be attached to this character, they might be divided into several 
Sub-genera. My observations have not been sufficiently exten- 
sive, to enable me to determine whether a classification founded 
upon agreement in the general dental arrangement of the pala- 
tines in this class, would be natural or coincident with one based 
upon a general correspondence in all the generic characters. Fu- 
ture investigation may settle that point. At all events it is believ- 
ed that the modifications in the arrangement of the palatine teeth 
from their constancy will be found to be of essential importance 
in determining species, the more so from the admitted fact that 
the color of these animals (a character much employed for this 
purpose) is extremely variable. I shall content myself by sub- 
mitting the result of my investigations. The palatine teeth of 
the Salamandra erythronota, Raf., are arranged in two longitudi- 
hal palatine rows, slightly diverging as they proceed backward. 
This is the only species that agrees generically with the description. 
The Sal. interrupta, Gr., has two longitudinal patches of palatine 
teeth, each composed of several rows, nearly in juxta-position cen- 
trally. In the Sal. agilis, there is but a single longitudinal patch 
of palatines composed of several rows so arranged as to form very 
acute angles pointing forwards. The Sal. variolata, Gill., has be- 
Side an armation of the longitudinal palatine ridge similar to the 
last, two partial rows on the transverse palatine ridge, interrupted 
inthe middle, curved backward and joined to the longitudinal 
Patch. Those of the Sal. maculata, Gr., are similar to the last, 
but the longitudinal patch has fewer rows. The palatines of the 
Sal. rubriventris, Gr., differ only from the Sal. variolata in having 
the transverse and longitudinal rows separate. The Sal. bilineata, 
has no longitudinal rows, and the straight transverse row has a 
Vol. xxxvi, No. 2.—April-July, 1839. 41 
