120 ON THE PHYSIOGNOMY OF SERPENTS. 



no essential change, except the introduction of some new 

 genera ; on this account, we shall make our extracts from 

 this last work. Cuvier having classed in the order of the 

 Ophidians all reptiles without feet, it follows that beings 

 of an organization different from that of serpents, such as 

 the Anguis, the Psoudopus, the Ca3cilia, should enter into 

 its formation. The first family, that of Anguis, compre- 

 hends the genera Anguis, Pseudopus, Ophisaurus, and 

 Acontias. The second family, that of true serpents, is 

 divided into two tribes: — That of the double marchers, con- 

 taining the genera Am2)hisba?na and Tyj)hl()ps ; and that of 

 the serpents properly so called, embracing all the rest of 

 the Ophidians, is divided again into two sections. First 

 come the innocuous serpents, distributed into the genera 

 Tortrix, Boa, Coluber, and Acrochordus, genera which may 

 very well be called families, and of which the majority are 

 composed of several very natural subgenera : beside the 

 boa figures the Scytale coronata, the Eryx, and Ilerpeton ; 

 with the Colubri are confountled the Pythons, the Honui- 

 lopsis,*theXenopeltis, the Heterodon, the Tree-snakes, and 

 the Oligodon. The venomous snakes are subdivided into 

 the venomous properly so called, in which the fangs are 

 isolated, and the venomous in which the dangerous wea- 

 pons are followed by several solid teeth. The first of 

 these two families is established for the reception of the 

 Crotalus, the Trigonocephalus, the Vipera, the Naja, the 

 Elaps, the Platurus, the Langaha, and several other new 

 subgenera, but of too little importance to be here enume- 

 rated ; the second comprehends the Bungarus, the Sea- 

 snakes, and the Acrochordus, under the name of Chersy- 

 drus ; the Csecilia, as a third tribe, terminates the order 

 of Ophidians. In passmg this classification in review, we 

 shall limit ourselves to remark, that Cuvier, attaching too 

 much importance to the dentary system of serpents, and 

 to the form of the under scuta, departs in several respects 

 from the natural system. At least, it seems to me, that 

 a union such as that of Hydrophis, of Bungarus, and Acro- 

 chordus, cannot be suitable to any method, natural or 



* Genus Cerberus of M. Cuvieb. 



