186 BATRACHIANS. 



ft External branchiae and gill clefts persistent through life ; no 

 eyelids PBOTEIDA, Y. 



W. FAMILIES OF ANURA. 



* Fingers and toes tapering or cylindrical, not dilated into a disk 



at their tips. 



f With teeth in the jaws ; toes completely webbed. 

 a. No spur at the heel ; fingers often webbed ; chiefly aquatic. 



RANIDJS, 77. 



aa. One of the bones of the heel forming a sharp, flat-edged 

 spur ; fingers scarcely webbed ; chiefly terrestrial. 



SCAPHIOPIDJE, 78. 

 j-f Jaws toothless ; toes webbed ; skin more or less warty ; ter- 



restrial BUFONID^E, 80. 



** Fingers and toes dilated at their tips, forming a viscous disk ; 

 arboreal HYLID^E, 79. 



X. FAMILIES OF URODELA. 



* No spiracles or openings in the. sides of the neck in the adult. 



* Sides (in our species) with a row of round red or yellowish spots 

 which are bordered with black (these very rarely obsolete) ; 

 belly dotted with black ; tarsus and carpus ossified ; verte- 

 brae opisthocoelian (not biconcave). PLEUKODELID^E, 81. 

 ff Spots, if any, not as above. 

 J Carpus and tarsus cartilaginous ; tongue much smaller and 



more extensively free than in the next, 

 a. Vertebras concave behind only (opisthocoelian.) 



DESMOGNATHID^, 82. 

 aa. Vertebrae biconcave (ainphiccelian.) 



PLETHODONTIIXE, 83. 



\\ Carpus and tarsus ossified ; vertebrae arnphicoeliau; tongue 

 large, thick, papillose, attached by its base, with a narrow 

 free margin ; salamanders usually of large size and dark 



colors AMBLYSTOMIDJE, 84. 



** With a spiracle or rounded opening in each side of the neck : 



size large. 



I, Limbs well developed ; toes 4-5. . . MENOPOMIDJE, 85. 

 lib. Limbs rudimentary ; toes 2-2 or 3-3. . AMPHIUMID^E, 86. 



