154 VERTEBRATE ANIMALS OF THE UNITED STATES 



lasts 3 or 4 months; the second lasts 2 or 3 years, and at the end of it 

 the animal again becomes aquatic. 



T. dorsalis (Harlan). Similar to T. viridescens, but with the red 

 spots forming a continuous or a broken line: coastal plain of North 

 and South Carolina. 



T. meridionalis (Cope). Similar to T. viridescens, except that 

 instead of the red spots there are black ones on both trunk and tail: 

 southern Georgia to Mexico, on the coastal plain. 



T. torosus (Eschscholtz). Body rather stout; tail long, with a 

 wide keel above and below; color brown above and yellow beneath; 

 length 170 mm.; tail 92 mm.: Pacific slope, from Alaska to Lower 

 California, in ponds and streams; no terrestrial form present. 



Family 5. Plethodontidae. — Body of medium or small size and 

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

 dwelhng species; a transverse (gular) fold just in front of the fore legs; 

 parasphenoid and vomerine teeth present (Fig. 72); costal grooves 

 II to 21; veretbrae amphicoelous 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-dwelling salamanders. 



bi Adult without gills; in Missouri 9. Typhlotriton. 



\>2 Adult with gills; in Texas 10. Typhloniolge. 



a2 Salamanders which are not blind 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. 



Ci With a light line running from the eye to the 



angle of the mouth i. Desmognathus. 



6-2 No such line present. 



fi Vomerine teeth absent 2. Leiirognathus. 



f2 Vomerine teeth present. 



gi Vomerine teeth continuous with the 



parasphenoid teeth 8. Stereochilus. 



