204 



HUMAN ANATOMY. 



Orbital surface 



F'lG. 22S. 



Orbital process 



^-^ 



Sphenoidal 

 process 



Outer surfa-ce 



Inf. turbinate crest 



Nasal crest 



Post, nasal 

 spine 



HORIZONTAL PLATE 

 For int. pterygoid plate 



Right palate bone from behind. 



Spheno-maxillary fossa 

 Spheno-palatine notch 



ERTICAL PLATE 



For ext. pteryg. 



plate 

 Pterygoid fossa 



TUBEROSITY 



After the loss of the teeth from old age or otherwise the alveolar process is 

 absorbed. Senile atrophy is particularly marked in this bone. 



THE PALATE BONE. 

 This' consists of a horizontal s^nd a vertical plate and three processes, \.\\e Py- 

 ramidal, the orbital, and the sphenoidal. The horizontal plate ' is quadrilateral. It 



completes with its fellow the hard 

 palate, filling the space left vacant be- 

 tween the back parts of the superior 

 maxillae. Its superior surface is 

 smooth like the rest of the floor of 

 the nares, and the lower rough, but 

 less so than that of the superior max- 

 illa. The anterior border ^ts the back 

 of the palatal process of the maxilla ; 

 the inner border is rough to meet its 

 fellow, and raised into a nasal crest 

 meeting the back of the lower edge 

 of the vomer. This is prolonged 

 behind to form with the other the 

 posterior 7iasal spine. The posterior 

 border is smooth and concave from 

 side to side. The outer border joins 

 the vertical plate.^ This is very 

 thin, with an outer and an inner sur- 

 face. It is surmounted by two processes, between which is a deep notch which 

 forms three-quarters or more of the spheno-palatine foramen*^ when the bone is in 

 position, so that both processes touch the body of the sphenoid. The outer surface 

 presents near the top a smooth vertical surface forming part of i\\e pterygo-maxillary 



Fig. 229. 



For ethmoid Orbital process 



To complete 

 ethmoidal cells 



Spheno-palatine 

 foramen 



Sup. turbinate crest 



Sphenoidal process 

 Middle nasal 

 meatus 



Inf. turbinate crest 



Inferior meatus 

 Tuberosity 



Posterior nasal spine 

 Nasal crest 



Inner aspect of right palate bone in place. Part of inferior turbinate removed. 



fissure. This narrows below into a groove which makes the posterior palatine 

 canal when applied to the corresponding groove in the maxilla. In front of this 

 the surface is at first rough where it rests against that bone, and more anteriorly 

 smooth where it closes the lower part of the opening of the antrum by an irregulal 



^ Os palatinum. ° Pars horizoatalis. '' Pars pcrpendicularis. ^ Foramen sphenopalatinum. 



Ant. part of inf. 

 turbinate 



