SKELETAL SYSTEM. 637 
the mouth, covering the vomers, and determining the position of the 
posterior nares—at the very back cf the mouth ; an os transversum or 
transpalatine extends between the maxilla and the junction of palatine 
and pterygoid; a postorbital rod (epipterygoid or columella) is formed 
by a downward process of the postfrontal meeting an upward process 
from the jugal ; the quadrate is large and immovable ; there are large 
Fic. 350.—Crocodile’s skull from dorsal surface. 
p.mx., Premaxilla; mzx., maxilla; 2, lachrymal; 47.4, prefron- 
tal; j., jugal; 2.4, postfrontal; g.7., quadrato-jugal; ¢., 
uadrate; sg., squamosal ; Ja., parietal; e.¢., epipterygoid 5 
ZR frontal; 4z., pterygoid (on lower surface); 0.¢., os trans- 
versum (on lower surface); #., nasal. 
parotic processes ; the tympanic cavity is completely bounded by bone s 
the teeth, which are borne by premaxillze, maxillee, and dentaries, are 
lodged in distinct cavities ; beside and eventually beneath the teeth lie 
reserve ‘‘ germs” of others. 
Each ramus of the mandible consists, as in most Reptiles, of a 
cartilage bone—the articular— working on the quadrate, and five 
