FROGS. 11 



WESTERN SPECIES. a 



The western species are somewhat confusing. At present Camp 

 (1917) recognizes three species, while Cope (1S89) held there were four.'' 

 The three species are Piana boylii, the yellow-legged frog ; Rana pretiosa, 

 the western frog; and Rana aurora (both aurora and draytoni), the 

 so-called "western bulKrog." 



Yellow-Legged Frog. — The yellow-legged frog has the ear or 

 tympanic region not darker than the rest of the head, possesses no 

 red in its coloration, and has the fold along the upper lip colored like 

 the rest of the body. These creatures are 2 1^ to 3 ^ inches in length 

 and occur in California. They have been less used for food because of 

 their skin secretions. 



Western Frog. — In the western frog the hind leg, when brought 

 forward along the body, has the inner angle of the bent heel reaching 

 to the eje or nostril, but never beyond. The back and top of the 

 head has prominent, inky-black spots. This species attains a length 

 of 3 to 4 inches and extends from Nevada and northern California 

 throughout Oregon and Washington to Alberta and east into Mon- 

 tana, Wyoming, and Utah. 



"Western Bullfrog." — The "western bullfrog" (PI. II, fig. 2), 

 unlike the western frog (R. pretiosa,), has no inky spots on the 

 back and top of the head, and the heel reaches to or beyond the 

 nostril. These creatures may have their skin very smooth {aurora) 

 or roughened (draytoni), have the lateral folds of the back indistinct 

 (aurora) or prominent (draytoni), possess unspotted or dotted backs 

 (aurora) or have regularly placed, light, centered spots (draytoni), 

 be medium, 3 inches long (aurora), or large, 4 inches (draytoni). 

 The "western bullfrog" extends from Puget Sound to Lower Cali- 

 fornia, 



These last two forms, the western frog and the "western bullfrog," 

 usually have the tympanic region darker than the rest of the head, 

 red often present in the coloration, and the fold along the upper lip 

 usually white or lighter than the rest of the head. 



POSSIBLE MARKETABLE SPECIES (PL. IV). 



There are several species of true frogs which are smaller, such as 

 the wood frog and its relative, the northern wood frog; the mink frog 

 (Rana septentrlonal/is) of extreme northeastern LTiiited States and 

 Canada; the carpenter frog (R. virgatipes) of New Jersey and the 

 Carolinas; or the local and rare gopher frog (R. scsopus) of Florida. 

 It will, doubtless, never become feasible to use these species in frog 

 culture. 



The wood frog (PL IV, fig. 3) is either light or reddish brown 

 above, with a darker brown streak or mask on either side of the head. 

 Underneath it is a glistening white. The northern wood frog is like 

 the wood frog ; but the length of the hind leg to the heel does not 

 exceed the combined length of the head and body, while in the 



a The author is indebted to Charles Lewis Camp's " Notes on the systematic status of the toads and frogs 

 of California " (University of California Publications in Zoolot;y, vol. 17, No. 9, pp. 115-125, Feb. 3, 1917, 

 University of California Press, Berkeley ) for most of what follows on the western forms. The author 

 also has specimens from the Pacific coast collected by Profs. J. C. Bradley, W. A. Hilton, A. C. Chandler, 

 anM the writer. 



6 Cope, E. D.: The Batrachia of North America. U. S. National Museum Bulletin No. 34, 432-447 

 Washington, 1889. 



