OF THE OPHIDIANS IN GENERAL. 



It is usual to comprehend under the denomination of 

 Serpents, all those reptiles which, along with a total want 

 of extremities, have a very elongated form of body. A 

 more rigorous examination, how^ever, demonstrates, that 

 among animals which on such principles it would be ne- 

 cessary to class with serpents, some present, in their general 

 organization, peculiarities that separate them in every re- 

 spect from serpents, to which they bear no resemblance, 

 except in their lengthened forms. It was reserved for our 

 times — thanks to the researches of the anatomist ! — to ar- 

 range among Batrachians some of those anomalous beings, 

 the greatest part of which have been jumbled together in our 

 systems. In casting a rapid glance over the great series 

 of reptiles whose bodies are covered with scales, we dis- 

 cover that these animals, with the exception of the tortoises, 

 are modelled on two types, familiarly known by the desig- 

 nation of Saurians and Ophidians. But in comparing 

 these animals with each other, we perceive that the more 

 or less elongated body exists in them in every degree ;* 

 that the development of the extremities diminislies in pro- 

 portion as the species to tlie second type ; that the function 

 of the ribs, as organs of locomotion, augments in the same 

 degree ; that species much allied present sometimes gi'eat 

 disparities in the arrangement of the extremities, or even 

 are only distinguishable from each other by the want or 

 presence of extremities ; t in a word, that the function 



* The Scinks, the Seps, the Pygodactylus, the Monodactylus, the 

 Pygopus, the Chalcis, the Tetradaclylus, the Ophisaurus, the Pseudo- 

 pus, &c. 



t The Amphisbaena and the Chirotes. 



