ORDER BATRACHIA. 481 



a simple fibrous membrane ; their internal orifice is on each 

 side, near the commissure of the lips between the lip and 

 the palatine teeth ; there is neither mastoidean, pterygoidean, 

 jugal, upper occipital, nor basilary bone. 



In the palate under the anterior and lateral portions of the 

 sphenoid and the orbital bones, are seen two thin plates all 

 bristling with crooked teeth, and which might be taken for 

 vestiges of vomeres or palatines, or of palatines and ptery- 

 goideans. The first of these plates has from six to seven 

 ranges of these teeth, while the smallest has but four. 



The hyoid bone of the siren is the same as that of the 

 larva of the salamander, but very much ossified in many of 

 its parts. 



The bones of the carpus are cartilaginous. 



The vertebrae are more numerous than those of the sala- 

 mander, and diff*erently figured ; their bodies, which corres- 

 pond by concave faces, are united by cartilages formed like a 

 double cone, as in fish. There are but eight pairs of ribs. 

 The eye is very small, and the ear concealed. 



END OK REPTILES. 



VOL. IX. II 



