NORTH AMERICAN BATRACIIIA AND REPTILIA. 7 



present or absent Menopomidce. 



B. Teeth on posterior or inner margin of palatines; no 

 anterior axial bope; gill-clefts closed in completely developed 

 specimens. 



a. Vertebrae ampliicu^lian; parietals embracing frontals; 

 palatines with teeth on their posterior portion, not pro- 

 longed over parasphenoid; occipital condyles sessile. 

 X. Carpus and tarsus osseous; parasphenoid without 

 dentigerous plates ; pterygoids present ; pre- 

 frontals prolonged and embracing frontals. 



Amhtystomid(P. 



y. Carpus and tarsus cartilaginous ; parasphenoid 



with dentigerous plates; pterygoids wanting; 



prefrontals not prolonged or embracing frontals. 



Plethodontid(B. 

 h. Vertebrae opisthocielian; parietals not embracing frontals. 

 X. Carpus and tarsus cartilaginous; jjalatines with 

 teeth on their posterior portion, not prolonged 

 over the dentigerous parasphenoid; pterygoids 

 and prefrontals wanting; occipital condyles ped- 

 icellate DesmognathidcB. 



y. Carpus and tarsus osseous; palatines with teeth on 

 the inner margin of the separate processes wdiich 

 extend backward over the non-dentigerous par- 

 asphenoid; pterygoids and prefrontals present; 

 occipital condyles sessile Pleurodelidip. 



Artificial Synopsis of Families. 



A. An opening on side of neck. 



a. Limbs small; toes 2-2 or 3-3 AmphiumidcB. 



h. Limbs w^ell developed; toes -1-5 Menopomidw. 



B. No opening on side of neck when completely developed. 

 a. jS'o patches of teeth (parasphenoid) on middle of roof of 



mouth behind; one or more series (palatine), usually 



transversely arranged, in front Amhlyatomidw. 



h. Patches of teeth (parasphenoid) on middle of mouth 

 behind. Without a row of large red spots on the sides. 

 X. Characters not combined as in the following. 



Plethodontid(n. 

 y. Anterior margin of tongue attached; toes 4-5; 

 costal folds not over 15; tail compressed and 

 tinned above and no dorsal band, or parasphe- 

 noid patches of teeth well separated and a yel- 

 lowish dorsal band Desmognathidm 



