AMPHIBIANS 143 



length 100 mm. ; tail 50 mm. ; costal grooves 12 ; vomerine teeth in 3 or 4 

 transverse patches; digits very long: northern California to British 

 Columbia and eastward into Montana and Iowa. 



A. annulatum Cope. Body slender; tail very long; color dark 

 brown above, with about 15 light cross bands, very light beneath; length 

 186 mm.; tail 94 mm.; costal grooves 13; tail with 31 grooves; vomerine 

 teeth in 2 patches: Arkansas and Missouri; rare. 



Family 4. Plethodontidae. — Body of medium or small size and 

 without gills or gill slits in the adult state, except in certain cave 

 dwelling species; parasphenoid and vomerine teeth present (Fig. 72); 

 costal grooves 11 to 21 ; vertebrae amphiccelous or opisthocoelous; carpus 

 and tarsus cartilaginous; lungs absent; ypsiloid cartilage absent; naso- 

 labial groove present (Fig. 64): about 16 genera and 50 species, all 

 American but two, which occur in Italy. These salamanders cannot 

 float in water without swimming motions, and are, with few exceptions, 

 terrestrial animals, living in shaded, moist localities near or in small 

 streams. In several genera the larvae are also terrestrial, losing their 

 gills before they hatch, or very soon after, and never entering the 

 water; the larvae of Desmognathus, however, make for the water, in 

 which they live about a year. 



Key to the Genera of Plethodontidae 



ai Blind, white, cave-dweUing salamanders. 



bi Adult without gills; in Missouri 9. Typhlotriton. 



hi Adult with gills; in Texas 10. Typhlomolge. 



ao Salamanders which are not Wind or white in color, 

 bi Tongue attached at its anterior margin. 

 Ci Hind foot with 5 toes. 



di Teeth not confined to the front of the jaw. 



ei With a light line running from the eye to the angle 



of the mouth i. Desmognathus. 



62 Xo such line present. 



fi Vomerine teeth absent 2. Leurognathus. 



fi Vomerine teeth present. 



gi Vomerine teeth continuous with the para- 

 sphenoid teeth 8. Stereochilus. 



go Vomerine teeth separated from the para- 

 sphenoid teeth. 



hi Palm without plantar tubercles 3. Plethodon. 



h.2 Palm with 2 plantar tubercles 5. Ensatina. 



do Front teeth alone present and projecting from the 



closed mouth 6. Aneides. 



c-2 Hind foot with 4 toes. 



di In the eastern States 4. Hemidaclylium. 



do On the Pacific slope 7. Batrachoseps. 



