176 BATRACHIA : URODELA. XXVI. 



This group is divided by Cope into 7 families, all but one of these 

 (Salamandridce} being represented in our fauna. These families 

 are based chiefly on technical characters, most of which can be 

 ascertained only by a careful study of the osteology. " It may be 

 stated as characteristic of the Batrachia in general that their char- 

 acters cannot be determined without a study of the skeleton." 

 {Cope.) (ovpd, tail; 77X05, visible.) 



Families of Urodela. 



a. Side of neck with a spiracle or rounded opening; no eyelids; vertebrae 

 amphiccelian ; teeth on front or outer edge of palatines. 



b. Limbs rudimentary ; body eel-shaped AMPHIUMID.E, 99. 



bb. Limbs well-developed ; body not eel-shaped. CRYPTOBRANCHID^E, 100. 

 aa. Side of neck without spiracle in the adult; limbs well developed; eyelids 



present; teeth on posterior or inner edge of palatines, 

 c. Palatine teeth in a transverse (or posteriorly converging) series, in- 

 serted on posterior portion of vomer. 

 d. Vertebrae amphicoelian (double concave). 



e. Parasphenoid (behind vomer) without teeth; carpus and tarsus 

 ossified ; tongue (in our species) large, thick, with radiating folds, 

 its margin little free ; digits 4-5. . AMBLYSTOMATID^E, 101. 

 ee. Parasphenoid with teeth ; tongue small, and largely free. 



PLETHODONTID.E, 102. 



dd. Vertebras opisthoccelian (concave behind only) ; teeth on parasphe- 

 noid ; palatine teeth often wanting ; tongue moderate, largely 



free ; toes 5 DESMOGNATHID.E, 103. 



cc. Palatine teeth in two longitudinal series diverging behind, inserted on 

 inner margin of two palatine processes ; parasphenoid toothless ; 

 vertebras opisthocoelian ; skull with a bony post-fronto-squamosal 

 arch ; tongue small, laterally free. . . . PLEURODELID^E, 104. 



FAMILY XCIX. AMPHIUMID^S. (THE CONGO SNAKES.) 



Body elongate, eel-shaped ; limbs rudimentary, with 2 or 3 toes 

 each ; a spiracle on each side of neck ; tongue indistinct, wholly 

 adherent ; a strong series of vomerine teeth parallel with the teeth 

 in jaws. Tail short, compressed. One species, inhabiting the 

 ditches and streams of the S. U. S. 



252. AMPHIUMA Garden. (Name unexplained.) 



490. A. means Garden. CONGO SNAKE. Blackish. L. 3 feet. 

 Ark. to N. C. and S. (Lat., swift-moving.) 



FAMILY C. CRYPT OBRANCHID^E. (THE GIANT 

 SALAMANDERS.) 



Body robust, with well-developed limbs ; an orifice on each side 

 of neck usually persistent throughout life ; tongue covering floor of 

 mouth; vomerine teeth strong; nostrils very small; no external 



