American Amphibia. 321 



class, by which the ordinal character of M. Brongn. is invalida- 

 ted,) thus Rana and Hyla are distinguished froip 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 ob";3rvation, 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- 

 nal 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 

 in the middle, curv^ed 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 



