28 lUJLLKTlX ol, rXITKI) STATES NATIONAL MUSKUM. 



H 



The animal is not coinnK 

 National ."Museum. 



)ii ill <"olloctions, and tlit'io are but four in tlio 



on 

 Ic 



Tiic j-cncial form is mncli like that of the X muculatus, but the muz- 

 is (IHlerent. I nsteail (tf bein^' depressed or even coucavc above, iunl 

 ratiier wide, it is itinclicd at the si(b's,soas to be ratherelevated at the 

 -nd,an(l tohave atnincate jirolile. 'J he head is wide in proportion to its 

 enytii, tlic two measurements hein;;- about e(iual. The length of the 

 taiNs the same as in S. nKicnlaliis, twice its length marking a point pos- 

 terior to tluM'.ve. The limbs an' not quite so hing as in the N. maciilatiis, 

 the spaee between them, when they are ai)pressed to the sides, oquabug 

 twice the extent of the antciior leg, wliich is little longer than the pos- 

 terior, in the specimens in the IMnseum the body is decidedly com- 

 pressed, and (here is a distinct median doisal groove. These char- 

 a(!ters aie less marked in the .V. muniUiliis. 



The upper li^) is more iieiidulous than in X maciiJatuN, or perhaps 

 sueh an appearancto may bo ascribed to an elevation of thepremaxillary 

 liorder, in accord with the more elevated muz/.le T!:e nostrils are 

 a little closer together than in the larger species, the distah ,'e between 

 them e(pialing half the interorbital spa(;e, nistead of two thirds. How- 

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

 l)etweeu the orbits. The brancthial processses are relatively considei ■ 

 ably longer than in X inncuhitKs in all the specinuMis, and they aic 

 more a(!umiuate in form. Tiieir length (tonsitlerably exceeds that of 

 the muzzle in fr(»nt of the eye. In .V. maoulntuH they are usually 

 shorter than this length ; in two or three specimens, however, they arc 

 as long as in the X7>HHr/r(/H.s'. There are but two branirhial lissur.'s. 

 The width of the head enters .").() times the length of the head and body 

 together. 



The numbers of the teeth furnish distinctive characters foi' this 

 sjiecies. They are: Premaxillaiies, 0-S; vomeropalatiues, 8-!> ; i)tery- 

 goids, (J. Thus while the pterygoids are as numerous as in X maciddhis, 

 the numbers of the other teeth are reduced. There are eleven <Ienta 

 ries and three spleuials in the lower Jaw. The j)o>!terior uares aie a 

 longitudinal slit opposite the space between the vomeropalatine teeth 

 and the pterygoids. The tongue is short ami roumled,and extensively 

 fr.ein front. The phalanges of the anterior foot are, L'-L'-I-'J. The 

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

 middle toes are equal, and the external and internal ones are e(pial. 

 The posterior phalanges number 2-2-3 -L', and the digits are all unequal, 

 and are very slightly webbed at the base. 



The skin is entirely smooth. The lateral tblds number fourteen, as i n .V. 

 inneulalus. The muscidar part of the tail has a wide, free, dermal border 

 above and lielow, The fonner is more slender than in most specimens 

 of the .V. Dutciihitiis; but this charac^ter does not always hidd good. 

 There are five cloacal papilla-, with the three anteri.u' iinelv fringed, 

 as in N. Maciilatus. 



