AMERICAN FROGS OF THE GENUS RANA. 459 



2 phalanges of fourth free, the web thicker and with convex border 

 in the breeding male; the web extending about halfway between the 

 outer metatarsals; subarticular tubercles moderate or rather small 

 and feebly prominent; no tarsal fold; inner metatarsal tubercle very 

 prominent, rather hard, sometimes feebly compressed, f to f the length 

 of the inner toe; a small, round outer tubercle present or absent. 



Skin of upper parts smooth or with small flat glands; a narrow or 

 moderately broad, prominent glandular dorso-lateral fold, from above 

 the tympanum to the hip; these folds parallel or slightly converging 

 on the anterior part of the back, where they are separated from each 

 other by a space contained 4^ to 5| times in length from snout to vent; 

 a glandular fold from below the eye to above the arm. Lower parts 

 smooth, posterior half of thighs with large flat granules; the posterior 

 part of the belly sometimes also granular. 



Grayish or pinkish brown above, without or with small dark brown 

 or black spots; a dark brown or black streak from the end of the 

 snout to the eye and a large blotch of the same color on the temple, 

 or loreal region and lower half of eye dark like the temple; a light 

 streak on the upper lip, from the end of the snout to the extremity of 

 the glandular fold behind the mouth; a V-shaped dark marking 

 sometimes present between the eyes; dorso-lateral fold paler than the 

 ground color, often edged with blackish or with a series of small black- 

 ish spots, on the outer side; limbs with more or less regular dark cross- 

 bands. Lower parts white, posterior part of belly and hind limbs 

 yellow, throat and breast sometimes with small brown or gray spots. 



Male with internal vocal sacs, strong fore limbs, and a large pad on 

 the inner side of the first finger; the web between the toes more devel- 

 oped during the breeding season. 



Nasal bones small, oblique, widely separated from each other; 

 ethmoid exposed in front of the parietals and forming an obtuse angle 

 penetrating between the nasals. 



Tadpole not unlike that of R. agilis, with 4 upper and 4 lower 

 series of labial teeth, viz. a long upper marginal and 3 short laterals; 



3 continuous lower and one (the innermost) interrupted. 

 Eggs as in R. temporaria, but smaller. 



Habitat. — Eastern North America, from Manitoba, Ontario, and 

 Quebec to South Carolina. 



This species is strikingly similar to R. agilis in form, color, and 

 habits, but the presence of vocal sacs in the males fully justify the 

 specific separation; it remains much smaller. Some specimens appear 

 to be connectant between it and R. cantabrigensis, and I am not fully 



