66. With a ventral disc; tympanum a little higher than wide; thighs not spot' 



ted behind; voice like a bark 



Eleutherodactylus latrans (Cope) Texas Cliff Frog 

 (Lithodytes latrans Cope) 

 No ventral disc; tympanum round; thighs spotted behind; voice like a 

 cricket's song 67. 



67. Diameter of the tympanum about half or less the diameter of the eye 



Syrrhophus marnoc\ii Cope Marnock's Frog 

 Diameter of the tympanum more than half the diameter of the eye 

 Syrrhophus campi Stejneger Camp's Frog 



68. Dorsolateral ridges broken or absent or extending only half way back 69. 

 With an unbroken dorsolateral ridge extending the length of each side of 



back 75. 



69. Tympanum inconspicuous, about half the si2;e of the eye, or covered with 



small tubercles; throat coloring not different in the two sexes 75. 



Tympanum smooth, usually quite conspicuous, that of the female being 

 about the si2,e of the eye, that of the male larger; throat of the male 

 usually yellow, or gray tinged with green, and usually of a different or 

 deeper color than that of the female 70. 



70. First finger distinctly longer than the second; belly usually mostly dark; 



throat of male usually gray, tinged with green; S. C. to Florida and 

 Miss. 



Rana hec\scheri Wright River-swamp Frog 

 First finger about equal to or shorter than the second; belly usually mostly 

 light colored; throat of male usually yellow 71. 



71. With two joints of fourth toe free of web; dorsolateral folds absent or 



extending about half way back 72. 



With one or no joint of fourth toe free of web; dorsolateral folds absent 



or interrupted 73. 



72. Dorsolateral folds extending about half way back; with much green about 



the head; west to Texas; introduced into Washington 



Rana clamitans Latreille Green Frog, Spring Frog 

 Dorsolateral folds absent; usually with dorsolateral light stripes; N. J. 

 to Georgia 



Rana virgatipes Cope Striped Sphagnum Frog, Carpenter Frog 



73. Body narrow; length of head and body more than two and one-half times 



width; fourth toe fully webbed; Georgia to Florida and Louisiana 

 Rana grylio Stejneger Southern or Lake Bullfrog 

 Body stout; length less than two and one-half times width; with one joint 

 of fourth toe free of web 74. 



74. Belly light yellow, unspotted; head narrow; length of head and body 



more than three times the width of the head; northern states from 

 Maine to Minn. 



Rana septentrionahs Baird Mink Frog 

 Belly silvery, faintly mottled with brown; head broad; length of head and 

 body less than three times the width of the head; our largest frog, get- 



352 



