18 PROr. HUXLEY ON THE SPECIFIC AND GENERIC 



border of the external uostril." — Owen, Fossil Beptilia of the 

 London Clay, Crocodilia, p. 15 : 1850. 



Miiller and Schlegel give remarkably clear and beautiful figures 

 of the skull of their Gravial ; and these show at once that the nasal 

 bones do not " reach the hinder border of the external nostril," 

 but meet the premaxillaries at a point very distant from that 

 border, viz. opposite the ninth tooth. Even did the nasal 

 bones reach the posterior boundary of the nostril, such a cha- 

 racter would not outweigh those derived from the relations and 

 number of the teeth, the structure and extent of the mandibular 

 symphysis, and the disposition of the dermal scutes, — all of which 

 are so clearly and definitely set forth by Miiller and Schlegel, that 

 it seems difficult to understand how any one who had consulted 

 the original memoir could have overlooked them. 



It was possible, however, that Miiller and Schlegel, notwith- 

 standing their great opportunities, might have erred in their 

 statements ; and I therefore gladly seized the opportunity of test- 

 ing their description by comparing it with an authentic skull of 

 the species in question, from New Guinea, in the collection of 

 the British Museum. 



I have found the statement of Miiller and Schlegel minutely 

 accurate in almost all points ; and there cannot be the slightest 

 doubt, not only that the Schlegelian crocodile is one of the Ga- 

 vialidce, but that it forms a distinct generic type in that family, 

 as different from Gavialis as Caiman is from Jacare, or Mecistops 

 from Crocodilus. 



The following are the most important measurements of the skull 

 of IthynchosucJius ScJilegelii in the British Museum collection : — 



Inches. 

 Length from the end of the premaxilla to that of 



OS quadratum 23 



Breadth from outer edge of one os quadratum to that 



of the other 8| 



Breadth across the face in front of the orbits 4 



„ at the 9th tooth 2 



„ at the 5th tooth li 



„ at the 3rd tooth IJ 



„ of the beak-like curved process which carries 



the two anterior teeth 1 



Mean width of lower jaw from symphysis to ex- 



. tremity IJ 



