28 BULLETIN 34, UNITED STATES NATIONAL MUSEUM. 



The animal is not common in collections, and there arc but four in the 

 National Museum. 



The general form is much like that of the N. maculatus, but the muz- 

 zle is different. Instead of being depressed or even concave above, and 

 rather wide, it is i)inched at the sides, so as to be rather elevated at the 

 end, and to have a truncate profile, 'i he head is wide in proportion to its 

 length, the two measurements being about equal. The length of the 

 tail is the same as in N. maculatus, twice its length marking a point pos- 

 terior to the eye. The limbs arc not quite so long as in the N. maculatus, 

 the space between them, when they are appressed to the sides, equaling 

 twice the extent of the nnterior leg, which is little longer than the pos- 

 terior. In the specimens in the Museum the body is decidedly com- 

 pressed, and there is a distinct median dorsal groove. These char- 

 acters are less marked in the -ZV. maculatus. 



The upper lip is more iiendulous than in N. maculatus, or perhaps 

 such an appearance may bo ascribed to an elevation of thepremaxillary 

 border, in accord with the more elevated muzzle. The nostrils are 

 a little closer together than in the larger species, the distance between 

 them equaling half the iuterorbital space, instead of two thirds. How- 

 ever, in one of the four specimens this sxDace measures two-thirds that 

 between the orbits. The branchial processses are relatively consider- 

 ably longer than in N. maculatus in all the specimens, and they are 

 more acuminate in form. Their length considerably exceeds that of 

 the muzzle in front of the eye. In N. maculatus they are usually 

 shorter than this length 5 in two or three specimens, however, they are 

 as long as mtXiQ N. punctatus. There are but two branchial fissures. 

 The width of the head enters 5.G times the length of the head and body 

 together. 



The numbers of the teeth furnish distinctive characters for this 

 species. They are : Premaxillaries, 6-8 ; vomeropalatines, 8-9 ; ptery- 

 goids, G. Thus while the i3terygoids are as numerous as in N. maculatus, 

 the numbers of the other teeth are reduced. There are eleven denta- 

 ries and three splenials in the lower jaw. The posterior nares are a 

 longitudinal slit opposite the space between the vomeropalatine teeth 

 and the pterygoids. The tongue is short and rounded, and extensively 

 IVcC in front. The phalanges of the anterior foot are 2-2-3-2. The 

 metacarpals are connected by a slight web to their distal ends. The 

 middle toes are equal, and the external and internal ones are equal. 

 The posterior phalanges number 2-2-3-2, and the digits are all uneqnal, 

 and are very slightly webbed at the base. 



The skin is entirely smooth. The lateral folds number fourteen, as i n N. 

 maculatus. The muscular part of the tail has a wide, free, dermal border 

 above and below, The former is more slender than in most specimens 

 of the JSf. maculatus ; but this character does not always hold good. 

 There are five cloacal papilhe, with the three anterior tinely fringed, 

 as in N. maculatus. 



