PALATE BOXE. 



49 



ascending process, for articulation with the inferior turbinated bone, 

 and behind that process the lachrymal groove. Behind the lachrymal 

 groove is the large opening into the sinus ; behind the sinus the sur- 

 face is rough for articulation with the palate-bone ; and traversing the 

 lower part of this roughness is a smooth groove, passing downwards 

 and forwards from the posterior margin, and completing with, the 

 palate bone the posterior palatine or palato-maxillary canal. 



The orlilal surface extends from the margin of the orbit to the 

 spheno-masillary fissure, and is bounded externally l)y the surface for 

 the malar bone, and internally by the lachrymal groove and a rough 

 edge which articulates with the lachrymal, ethmoid, and palate bones. 

 A groove commences in its posterior border, and leads forwards into a . 

 complete canal, the mfram'Mtal, which opens anteriorly at the infra- 

 orbital foramen. 



The maxiUanj sinus, or antrum of Highmore is a large cavity lying 

 above the molar teeth and below the orbital plate, lined in the fresh 

 state by mucous membrane, and communicating with the middle 

 meatus of the nose. Its orifice is considerably diminished by con- 

 tiguous bones, viz., by the uncinate process of the ethmoid, the inferior 

 turbinated bone, and the palate bone. 



THE PALATE BONE. 



The palate bone forms the back part of the hard palate, and the 

 lateral wall of the nose between the superior maxillary bone and 

 the internal pterygoid process. It consists of a horizontal and a 

 vertical plate united at a right angle, and of three processes, viz., the 



Fig. 41. — The Palate Bone op the Eight Side. Fig. 41. 



(A. T.) § 



A, from the outside and behind ; B, from the inside. 



1, the upper surface of the palatine plate ; 2, its 

 posterior curved border or palatine arch ; 3, posterior 

 nasal or palatine spine ; 4, the rough surface of adjacent 

 articulation rising superiorly into the vomeric crest in 

 A ; 5, 5, the nasal process ; 6, the ridge or shelf support- 

 ing the inferior turbinated bone ; 7, the sjjhenoidal 

 process ; 8, in B, the orbital process, showing a cellular 

 cavity ; 8', in A, its orbital surface ; 9, the spheno- 

 palatine notch ; 10, 11, 1'2, the pyramidal process — 10, 

 rough surface of union with the external j)terygoid plate, 

 11, with the internal plate, and 12, the inter-pterygoid 

 smooth surface ; 1-3, 13, groove of the palato-maxillary or 

 posterior palatine canal. 



pyramidal process, extending outwards and 

 backwards from the junction of the horizontal 

 and vertical plates, and the orbital and sphe- 

 noidal processes, surmounting the vertical 

 plate. 



The palate bone articulates with its fellow, 

 and with the superior maxillary, ethmoid, 

 sphenoid, vomer, and inferior turbinated bone. 



The horizontal or palate plate presents pos- 

 teriorly a thin free border, forming the limit of the hard palate, and 



A'OL. I, E 



g n 12^ 



