278 CROCODlLIDiE. 



iSyno^isis of the Sjjecies. 



1. Snout very slender, Gavial-like, at least twice as long as broad at 

 the base ; mandibular symphysis extending to the level of the 

 sixth, seventh, or eighth tooth ; prjemaxillo-maxillary suture, 

 on the palate, produced posteriorly. 



Nuchal scutes in two longitudinal series, 



continuous or subcontinuous with the 



dorsals 1. tatiq>hractus,'p. 27d. 



Nuchal scutes six, four in a square with 



one on each side, subcontinuous with the 



dorsals 2. johnstonii, p. 279. 



Nuchal scutes six, four in a square with 



one on each side, widely separated from 



the dorsals 3. intennedius, p. 280. 



II. Snout more than once and a half, and not more than twice and 



one fourth, as long as broad at the base ; mandibular sym- 

 physis extending to the level of the fourth or fifth tooth ; 

 pra?maxillo-maxillary suture, on the palate, produced poste- 

 riorly. 



A. No longitudinal ridge in front of the eye ; anterior nuchal 



scutes (postoccipitals) well developed. 



A longitudinal swelling or ridge along the 



middle of the snout 4. americanus, p. 281. 



A longitudinal ridge between the orbits, 



none on the snout 5. sicunensis, p. 282. 



No ridges on the forehead or snout G. nihticus, p. 283. 



B. A longitudinal ridge in front of the 



eye; anterior nuchals usually absent. 7. 2'orosus, p. 284. 



III. Snout not more than once and a half as long as broad at the 

 base; mandibular symphysis extending to the level of the 

 fourth or fifth tooth ; prajmaxillo-maxillary suture, on the 

 palate, transverse or curved for^^■ards. 



A. Snout without ridges. 



Dorsal shield usually composed of four lon- 

 gitudinal series of scutes, the median of 

 which are broader than long 8. ^Hduatris, p. 285. 



Dorsal shield composed of six longitudinal 



series of scutes in the middle 9. rohustus, p. 286. 



E. A more or loss distinct oblique ridge in front of the eye. 



Scales on upper surface of limbs keeled . . 10. rhomhifer, p. 287. 

 Scales on limbs perfectly smooth 11. moreletii, p. 287. 



