380 LAKE SUPEKIOR. 



to the base of the last fingers. The fingers, however, are compara- 

 tively more slender, and those of the anterior foot more unequal 

 when compared to each other. 



The head is rather prominent, the snout, however, being rounded. 

 The nostrils, which are very small, open at its extremity. The eyes 

 are circular, and of medium size, slightly prominent. The upper 

 eyelid rises to the greatest height of the head. The tympanic circle 

 is very large, and very near the orbit. The mouth, widely split, is 

 provided with acute teeth upon the whole margin of the upper jaw. 

 There is also a small group of teeth, in pairs, upon the palatal bones. 

 The tongue is broad, oblong, pear-shaped, lining the whole floor of 

 the mouth from the symphysis of the lower jaw ; it terminates back- 

 wards in two obtuse lobes. 



The body is proportionally long, ovate, the head forming one-third 

 of the whole length. A cutaneous keel, of the same color as the 

 main hue of the back, extends on both sides from the posterior angle 

 of the orbit to the anus. The posterior limbs are longer than the 

 whole body by the whole length of the feet. The thighs are com- 

 paratively thick and short. The anterior limbs bear the same pro- 

 portion to the size of the whole body that are usually observed in 

 the various species of frogs. Figs. 4 and 5 give, not only an accurate 

 idea of the general appearance of the animal, but the proportional 

 thickness and length of the toes are drawn with the greatest 

 minuteness. 



The largest specimens I have collected are about one-fourth larger 

 than the figures. The color is of a blackish brown upon the whole 

 upper surface of the body, head and limbs. Irregular, deep black 

 spots, of an angular form, are dispersed over this whole surface ; they 

 are very small upon the head, but larger upon the back, and largest 

 upon the hind legs. In large specimens, the general color is more 

 uniform, somewhat darker, and the spots less distinct. The whole 

 lower surface is either uniformly whitish, or witli a slight yellowish 

 tint towards the hind extremity, and frequently with small blackish 

 or brownish spots along the sides. The outline of the lower margin 

 is bordered with white. Specimens of this species were caught in 

 various localities along the northern shores of Lake Superior. 



