THE BATRACHIA OF NOR I'H AMERICA. 



407 



vocal vesicles. A glaudular ridge exteuds from the middle of the in- 

 ferior edge of the tympauic drum to a point above the middle of the 

 humerus. There are four thick glaudular folds ou the back, the exter- 

 nal or dorsolateral commeuciug above the tympauum. The thickness 

 of these ridges is much greater than in the B. virescens virescens, but in 

 some specimens of the B. v. hrachycei^liala they approach very closely in 

 form, and are in fact not distinguishable from those of individuals of this 

 species where the ridges are narrower than usual. In a few individuals, 

 of which the specimen described is one, there is another pair of ridges 

 near the middle line of the back. In all the specimens these a repre- 

 resented in the pelvic region by a pair of approximated ridges on each 

 side of the urostyle. 



The interorbital width is two-thirds the width of an eyelid. 



The tubercles of the palm are well developed. The first (second) fin- 

 ger is longer than the second, and equal to the fourth. The internal 

 cuneiform tubercle is small and weak, and is without acute edge. There 

 is a trace of an external tubercle. The toes are not fully webbed ; the 

 edges of the web are deeply scalloped, leaving two phalanges of the 

 fourth toe free, an 1 leaving only a narrow border to the distal half of 

 the antepenultimate phalange. 



V^ 



YiG. W2. Rana palustiis. No. 13403. Garrison's, N". Y.; i. 



Measurements of No. 13403. 



M. 



Length of head and body 070 



Width of head at posterior edges of tympana 027 



Length of head to posterior edges of tympana 023 



Length of fore limb 037 



Length of fore foot 016 



Length of hind leg to groin 115 



Length of tibia ■. 049 



Length of tarsus 020 



Length of remainder of foot 039 



