ANATOMY OF VERTEBRATES. 15 



scales. Teeth rendered complex by undulation and side branches 

 of the converging folds of cement, whence the name of the order. 



Genus Rhombopholis. 

 Labyrinthodon. 



Order XIV. BATRACHIA. 



Endoskeleton ossified ; two occipital condyles ; vomer divided, 

 in most dentigerous ; temporal fossre unroofed ; scapular arch 

 detached from occiput ; ribs as processes, or short, straight and free ; 

 skin nude, often lubricous. Limbs digitate, trisegmental. Intestine 

 without spiral valve, vent posterior to urethra. Embryonal gills, 

 in some retained, in most lost ; with a metamorphosis associating 

 a tail-less body with pulmonary respiration and a heart of two 

 auricles and one ventricle. 



Suborder I. Ophiomorpha. 

 Fam. CceciliadcB. Ex. Caxilia. 



Suborder II. Iciithyomorpha. 



Fam. Froteidce. Ex. Siren, Proteus. 



Salamandridce. Ex. Newt, Salamander. 



Suborder III. Theriomorpha. A aura. 



Fam. 1. Aglossa. Ex. Pipa or Surinam Toad. 



2. Ranidce. Ex. Frog. 



3. Hylidce. Ex. Tree-frog. 



4. Bufonidcs. Ex. Toad. 



Subclass V. Order XV. ICHTIIYOPTERYGIA. 1 {Extinct.) 



Body fish-like, without neck ; limbs natatory, with more than 

 five multiarticulate digits ; vertebrae many, short, biconcave ; no 

 sacrum ; anterior trunk -ribs with bifurcate heads ; an episternum 

 and clavicles ; post-orbital and supra-temporal bones ; a foramen 

 parietale ; maxillaries small ; premaxillaries long and large. 

 Teeth confined to maxillary, premaxillary, and premandibular 

 bones, implanted in a common alveolar groove, penetrated by 

 converging folds of cement at the base ; nostrils two, small, near 



1 Gr. ichihys, a fish ; pteryx, a fin. 



