AMERICAN FROGS OF THE GENUS RANA. 447 



Rana longipes Hallow., Rep. U. S. Explor. Surv., X, iv, Zool., p. 20, PI. 

 X, fig. 1 (1859). 



Rana nigricans, part., Brocchi, op. cit., p. 15. 



Rana aurora draytonii Camp, Univ. Calif. Publ. Zool., XVII, 1917, p. 123. 



Vomerine teeth in small oblique groups between or just behind 

 the choanse, close together or at least nearer to each other than to the 

 latter. 



Head broader than long, rather strongly depressed ; snout rounded, 

 feebly projecting beyond the mouth, as long as or a little longer than 

 the eye; canthus rostralis obtuse; loreal region oblique, feebly con- 

 cave; nostril equidistant from the eye and from the tip of the snout; 

 distance between, the nostrils equal to or a little greater than the inter- 

 orbital width, which is usually equal to or a little less than that of the 

 upper eyelid, but sometimes only f that width; tympanum very dis- 

 tinct, smooth, or, exceptionally, with a few granular asperities, f to 

 once the diameter of the eye, 1| to 2 times its distance from the latter. 



Fingers rather long, obtuse, with a more or less distinct dermal mar- 

 gin, first longer than second, third much longer than the snout; sub- 

 articular tubercles moderate. 



Hind limb moderate or long, the tibio-tarsal articulation reaching 

 the eye, the tip of the snout, or between these two points, the heels 

 overlapping when the limbs are folded at right angles to the body; 

 tibia 3| to 5 times as long as broad, If to 2ro times in length from snout 

 to vent, shorter than the fore limb, slightly or considerably shorter 

 than the foot. Toes obtuse, f to nearly entirely webbed, one or two 

 phalanges of fourth free; outer metatarsals separated nearly to the 

 base; subarticular tubercles small or rather small, moderately promi- 

 nent; tarsal fold more or less distinct; inner metatarsal tubercles oval 

 or elliptical, i to f the length of the inner toe; outer tubercle indistinct 

 or absent. 



Upper parts smooth or with small warts and pearl-like excrescences; 

 a more or less prominent, moderately broad glandular dorso-lateral 

 fold from above the tympanum to the hip or not quite so far, p arallel 

 with its fellow, from which it is separated by a space 3f to 5 times in 

 the length from snout to vent ; a glandular fold from below the eye to 

 above the arm, sometimes followed by a glandule; lower parts smooth, 

 hinder half of thighs coarsely granulate. 



Olive, brown, or reddish brown above, with moderately large round- 

 ish dark spots, which may be lighter in the center; a dark central 

 streak and sometimes a more or less distinct dark temporal spot; a 

 light streak from below the eye to the end of the glandular fold behind 



