reduced; not over three digits on each limb; row of teeth on vomer 

 paralleHng those on the maxillary 

 One genus — Amphiuma ( 1 species) Congo Snakes 

 Family CRYPTOBRANCHIDAE 



Body flattened, wrinkled; one pharyngeal gill slit on each side (in 

 native species) ; limbs well developed; row of teeth on vomer 

 paralleling those on the maxillary 



One genus — Cryptohranchus (2 species) Helbbender 

 (One other genus, Megalohatrachus, is found in Asia) 

 Family SALAMANDRIDAE (or Pleurodehdae) 



Teeth on diverging posterior extensions of the vomero-palatines, 

 which extend over the parasphenoids; no parasphenoid teeth 

 One genus — Triturus (7 species) Newts 

 Family AMBYSTOMIDAE 



With one transverse row of vomero'palatine teeth; no paras' 

 phenoid teeth 



Three genera — Dicamptodon (1 species) 

 Rhyacotriton (1 species) 

 Amhy stoma (12 species) 

 Family PLETHODONTIDAE 



With nasO'labial grooves; large patches of teeth on parasphenoid 

 Seventeen genera — 



Desmognathus (5 species) Haideotriton (1 species) 



Leurognathus (1 species) Stereoch-ilus (1 species) 



Plethodon (17 species) Typhlotriton (1 species) 



Ensatina (3 species) Ty phlomolge (1 species) 



Hemidactylium (1 species) Gyrinophilus (4 species) 



Plethopsis (1 species) Pseudotriton (2 species) 



Batrachoseps (2 species) Eurycea (8 species) 



Aneides (4 species) Manculus (1 species) 



Hydromuntes (1 species) 

 Suborder MEANTES 



Family SIRENIDAE 



Body elongate, snake-like; no hind limbs; front limbs much re 

 duced; premaxillary and dentary with horny sheaths; large patches 

 of teeth on vomer 

 Two genera — Siren (2 species) Sirens 



Pseudohranchns (1 species) Striped Siren 



KEY TO THE PRINCIPAL SPECIES OF SALAMANDERS 



1. With but one pair of legs; aquatic; Family Sirenidae 2. 



With two pairs of legs in the adult 4. 



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