THE BATRACHIA OF NORTH AMERICA. 209 



The tougue occupies but little space on the floor of tlie uioutb. It is 

 sligbtl}^ free at the sides, but not at the anterior or posterior ends, which 

 pass insensibly into the adjacent tissue. Its form is oval anterox)oste- 

 riorly. Ttje vomeropalatine teeth are iu two longitudinal series, which 

 converge anteriorly, and join after running close together between the 

 internal nares. The latter are about as far apart as the external nares. 



When applied to the side the fore limb overlaps the hind limb by the 

 length of the hind foot. While of nearl}^ the same length, the fore 

 limbs are not more that half as thick as the hind limbs. Their length 

 is just equal to the distance from the tixilla to the end of the muzzle. 

 The second (first) finger is very small, with but a rudiment free. The 

 third finger is long, and the fourth still longer, while the fifth is longer 

 than the second (first), but generally less than half as long as the fourth. 

 The phalanges are 1-2-3-2. 



The first and fifth toes are mere obtuse rudiments and of eiiual length. 

 The other toes are not relatively so long as the fingers, standing 2-4-3 

 in order of length, beginning with the shortest. The phalanges are 

 1-2-3-3-1. In males iu the breeding-season the hind legs are thickened, 

 especially the integument of the inner side. It is then divided by trans- 

 verse folds, and the portions between them become corneous or chit- 

 inous. There are thus from ten to twelve transverse plates on the in- 

 side of the thighs, and an irregular number on the inside of the tibia 

 and tarsus. The rudimental external and internal toes have a cap of 

 the same substance. These bodies aid the male in maintaining his hold 

 on the female during copulation. 



The skin in the form Viridescens is smooth on all the surfaces, but 

 rather closely wrinkled. The tail has a free dermal margin or fin (of 

 about equal width and length) on both the superior and the inferior 

 edges. The genitalia are very prominent at the breeding season, and 

 in the male the orifice is oval. It is very papillose, especially within 

 the anterior border. (See Plates 39 and 41, fig. 3.) There is no trans- 

 verse postgular fold, and there are no transverse lateral grooves. 



Measurements of No. 3795. 



ar. 



Total leugtli „„ , 090 



Leugth ofliead aud body 04Q 



Leogtb to groiu 036 



Length to axilla 016 



Leugtli to cautlius oris 006r) 



Leugth of fore-leg 0145 



Length of cubitus 005 



Leugth of fore-foot 0065 



Leugth of hiud leg 0175 



Length of tibia 0053 



Leugth of hiud foot 0088 



Width of head 008 



Width between orbi ts 0046 



Depth of tail at middle 0075 



1951 Bull 34 14 



