ON THE DERMAL ARMOUR OF JACARE AND CAIMAN 303 
Inches. 
Breadth at the: oth toOth: ssvasucin suse vasa settinessaacw@atnasarenmergansee 2 
i ai the Cth HOOtS cassie: sa ues datleiasiad Saataquissee ghuambaisaederason I} 
as AE THEE STCO OUI. 22.45 sa weaataaudetone aaiienan sauuennns eae nae 12 
Pr of the beak-like curved process which carries the two 
anterior teeth sccsis wasceussuaseasabie. wxtveneeabounaianers I 
Mean width of lower jaw from symphysis to extremity.. ......... 13 
Len gee - ssicspascgawnsrsmanapssnmmoandganss eas ape yale euamenntaahnsian dipstumigie 12 
5 
16 
The face is very smooth ; but a slight longitudinal groove runs 
down on each side from the anterior margin of the orbit for about 
two inches. Anteriorly to this point the snout retains a nearly even 
diameter as far as the ninth tooth, in front of which it suddenly 
narrows a little, retaining nearly the same dimensions to the fourth 
tooth, where it widens a very little, and then suddenly narrows 
to the terminal beak. The lower jaw does not expand at all at 
its extremity. The nasals join the premaxillaries opposite the ninth 
tooth, and the splenial bones, iu the lower jaw, end opposite the tenth 
mandibular tooth, as the figures of Miller and Schlegel show. The 
vomers appear between the inner edges of the palatines posteriorly, 
as a thin bony band 12inch long by $ inch wide, which tapers at each 
end and is divided by a longitudinal suture. The ninth tooth of the 
upper jaw is stronger than the rest. 
The only point in which the description of Miller and Schlegel 
seems to me to be incomplete! is with regard to the disposition of 
the teeth. They say—-‘ The teeth of C. Schlegeli, as regards their 
form and development, more nearly resemble those of the true Croco- 
diles ; but in the way in which the teeth of the two jaws are opposed, 
there is the most complete resemblance between our species and the 
Gangetic Gavial,—both which species differ from all other crocodiles 
in the circumstance that when the mouth is shut, all the teeth of the 
under jaw project outside the lateral margin of the upper jaw” 
(2. € p. 22). 
What I find is this:—The anterior teeth of both the upper jaw 
and the mandible are long, slender, sharp-edged, and slightly curved. 
The posterior eleven, on each side, in the upper jaw, are short, straight, 
conical, and constricted below their crowns. There are deep inter- 
dental pits between the ten posterior mandibular teeth, into which 
the opposed teeth of the maxilla are received when the jaws are 
closed. All the mandibular teeth, except the two anterior and the 
fourth pair, pass into like pits in the upper jaw. The anterior eight 
1 Or it is possible that the Rhyxchosuchus from New Guinea, which I have examined, is 
specifically distinct from the Bornean form. 
