70 ATLAS AND TEXT-BOOK OF HUMAN ANATOMY. 



Fig. 83. — The right palate bone seen from behind (\). 



Fig. 84. — The right palate bone seen from the outer surface (\). 



Fig. 85. — The right palate bone seen from the inner surface (\). 

 * = surface which completes the pterygoid fossa. 



Fig. 86. — The left nasal bone seen from the outer surface (\). 



Fig. 87. — -The left nasal bone seen from its inner surface ({). 



Fig. 88. — The right malar bone seen from the outer surface (\). 



Fig. 89. — The right malar bone seen from the temporal surface (\). 



of which perforate the pyramidal process and end on the hard palate as the lesser palatine 

 foramina. 



Of the three processes of the palate bone, the pyramidal process or tuberosity passes back- 

 ward from the junction of the two plates of the bone, filling in the pterygoid notch of the ptery- 

 goid processes of the sphenoid bone and completing the pterygod fossa. 



The other two processes, the orbital and the sphenoidal processes, are given off from the upper 

 portion of the perpendicular plate above the ethmoidal crest, and are separated from one another 

 by a deep notch, the sphenopalatine notch (Figs. 84 and 85). The inferior surface of the body 

 of the sphenoid bone converts this notch into the sphenopalatine foramen (Fig. 102), an important 

 communication between the pterygopalatine (sphenomaxillary) fossa and the nasal cavity, 

 which gives passage to vessels and nerves (see page 78). 



The orbital process (Figs. 83, 85, and 96) is the anterior and larger of the two processes, 

 and is directed outward. Its upper surface forms the most posterior portion of the floor of 

 the orbit, articulating with the lamina papyracea by the palatoethmoidal suture and with the 

 orbital portion of the maxilla by the palatomaxillary suture. Its anterior surface is closely 

 applied to the maxilla, while the internal one has an irregular boundary and articulates with 

 the ethmoid labyrinth, where it assists in closing in some of the ethmoidal cells, the palatine 

 cells. The orbital process is also in contact with the external surface of the body of the sphenoid 

 bone by the sphenoorbital suture, and forms the posterior portion of the inner margin of the 

 inferior orbital (sphenomaxillary) fissure. 



The thin posterior sphenoidal process (Figs. &$, 85, and 101), directed internally, is applied 

 to the ala vomeris, to the inferior surface of the body of the sphenoid bone, and to the sphenoidal 

 concha? (sphenoidal turbinated bones), and also partly closes the orifice of the sphenoidal sinus. 



The palate bone is formed in membrane in the third fetal month and is already ossified at about the middle of 

 the fetal life, but like the upper jaw it is rather short in the new-born. 



The orbital surface of the orbital process is sometimes unusually large, and the width of the perpendicular plate 

 is subject to great individual variation. 



THE ZYGOMATIC BONE. 



The zygomatic or malar bones (Figs. 88 and 89) are three -sided, flat, strong bones which 

 form the prominence of the cheek. They articulate with the frontal, sphenoid, and maxillary 

 bones (Figs. 37 and 38), and also with the temporal bone by means of the zygoma which bridges 

 over the temporal fossa (Figs. 39 and 40) (the sutures are described upon pages 37 and 80). 

 The small orbital plate, placed at right angles to the malar surface, assists in the formation of 



