16 PROF. HUXLEY ON TKE SPECIFIC AND GENERIC 



This excellent genus, as established by Dr. Gray, includes Cuvier's 

 Crocodiltis cataphractus (which Dr. Gray considers to be the yoimg 

 of a species whose full-grown form was discovered by Mr. Bennett 

 in West Africa), Crocodilus Journei and Crocodihis ScTilegelU. 

 As I have endeavoured to show, however, C. Journei is a true 

 crocodile ; and, as I shall point out below, MiiUer and Schlegel 

 have satisfactorily proved C. Schlegelii to be a Gavial. Conse- 

 qviently Mecistops is at present represented by only one species, 

 which must be called M. cataphractus if M. Bennettii of Gray is 

 really the adult of the form which Cuvier described. 



III. In the family of the Gavialid^, the snout is always very 

 long and slender ; the teeth are for the most part slender, sharp- 

 edged, and subequal. The two anterior mandibular teetli pass into 

 grooves, one of which lies on each side of a beak-like prominence 

 of the premaxillae, which carries the two anterior upper teeth. 

 The canines are received into grooves. The mandibular symphysis 

 extends back to at least the fourteenth tooth, and is partly formed 

 by the junction of the splenial bones. The premaxillo-maxillary 

 sutvu-e is always strongly convex backwards. The posterior nares 

 are situated more forward than in the Crocodili. The temporal 

 fossae are large. The feet are strongly webbed. The dorsal scutes 

 are not articulated ; and there are no ventral scutes. 



I distinguish two genera in this family, Rhyncliosuchiis and 

 Gavialis. 



G^nus 6. Ehynchosuchus. 



There are twenty teeth above, and eighteen or nineteen below, 

 on eacb side ; the mandibular symphysis extends to the fifteenth 

 tooth. The posterior teeth of the upper jaw, and almost all those 

 of the lower jaw, are received into interdental pits ; the orbital 

 margins are not raised ; and the premaxillse are hardly at all ex- 

 panded. The premaxillo-maxillary suture does not reach the third 

 tooth behind the notch. 



I propose the name RhyncJiosuchus to indicate that generic type 

 which is at present represented by the solitary species called by 

 MUller and Schlegel Crocodilus ( Gavialis) Schlegelii, and ad- 

 mirably described and figvired by them in their essay, ' Over de 

 Krokodilen van der Indischen Archipel,' in the ' Verhandelingen 

 over de natuurlijke Gesch. der Nederl. overzee. Bezittingen,' 

 1839-1844. Under the title Crocodihis (Gavialis) Schlegelii 

 (p. 18), they say — " The Gavial from Borneo, when compared with 



