in.] THE CRANIAL SKELETON. 119 



part of the perpendicular plate, are parts which have no bony 

 representatives in non-mammalian Vertebrates, with the ex- 

 ception of the Crocodiles. Only that part of each palate 

 bone which connects the body of the sphenoid with the 

 vomer and upper-maxillary bone (i.e. the sphenoidal and 

 orbital processes) is represented by the palatine bones of such 

 non-mammalian Vertebrates. 



FIG. 109. UNDER SURFACE OF A FOWL'S SKULL. (After Parker.} 



/'.>, basi -occipital ; en, points just in front of the anterior opening of the Eusta- 

 chian tubes ; J, malar ; mx, maxillary bone ; p, palatine bone ; pf, post-orbital 

 process ; //, pterygoid ; px, pre-maxilla ; q, quadrate bone ; qj, quadrato- 

 jugal ; so, supra-occipital ; v, vomer. 



In almost all those Fishes which have no osseous skull the 

 palate bones are represented by the anterior part of that 

 cartilaginous bridge, or flying buttress, which proceeds from 

 within the front of the mouth backwards and outwards to- 

 wards the point of suspension of the lower jaw, and which in 

 Sharks supports teeth and is called the upper jaw. 



Sometimes the horizontal plate has large defects of ossifica- 

 tion, as in many Marsupials and the Hedgehog. 



Often in Mammals the palatine may directly join the frontal 

 in the orbit, as in the Hog, Lemur, and Pteropus. It may 

 join the lachrymal, as in the Dog. It may extend in the orbit 

 between the lesser wing of the sphenoid and maxillary, and 



