Frogs. Ranidae: Rana 



Fig. 6. I. Nostril. 2. Internasal space. 3. Costal (dorsolateral) fold. 

 4. Enlarged thumb of male. 5. Enlarged tympanum of male. 6. Tym- 

 panum of female. 7. Tympanic fold. 8. Fleshy fold on jaw. 9. Glandu- 

 lar folds on tibia. 10. Sacral hump. 11. Full webbing of male bullfrog. 

 12. Narrow interorbital space. 13. Intertympanic space. 



a. Tympanum larger than eye in male, equal in female 

 (rarely smaller in R. virgatipes) (5.6-12.5 in L.); throat of 

 male differently colored; upper jaw unicolor; no black 

 mask; no light jaw stripe; no regular dorsal rows of spots; 

 no pronounced yellow, orange or red on undersides of 

 hind legs or on belly or groin; tibia 1.8-2.6 in L. 

 b. Rear of femur with alternation of light and dark hori- 

 zontal bands; dorsolateral folds absent; edge of jaw 

 uniform. 

 c. Size small 1 5/8-2 5/8 inches (41-66 mm.); usu- 

 ally a light yellowish dorsolateral stripe extends 

 back from eye; two joints of fourth toe free of web; 

 vocal sacs of male like a marble on either side of 

 head; intertympanic space 3.42-4.4 in L.; foot 

 with tarsus 1. 36-1. 56 in L. 



Carpenter frog. Rana virgatipes. Plate LXXIX. 

 cc. Size large 3 1/4-8 inches (82-200 mm.); no or only 

 one joint of fourth toe free of web; back uniform 

 in color; no vocal sacs in males on side of head. 

 d. Alternation of color on rear of femur con- 

 spicuous; first finger generally less than 

 second finger; intertympanic space narrower 

 (5-6.8 in L.); foot with tarsus shorter (1.4- 

 1.67 second; in L.). 



Southern bullfrog. Rana grylio. Plate LXVII. 



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