THE FACE 331 



others, one large foramen and a second smaller one much further back 

 on the palatal surface ; in others, one large foramen and two smaller 

 posterior foramina; and more rarely, the large foramen may be accom- 

 panied by three or even more smaller openings. It is not clear that all 

 these are the openings of accessory palatine canals ; usually not more 

 than two can be traced back to the posterior wall of the main canal. 



On the nasal surface of the bone, sometimes on the inferior or pal- 

 atal surface, near the posterior border, where the horizontal and vertical 

 plates meet, one foramen or several small foramina are often visible. 



In all the specimens examined the posterior palatine foramen was 

 always present, although in some cases it was reduced in size. In a 

 few of the bones a very small accessory foramen was seen on the 

 orbital surface just behind the large opening and appeared again 

 on the palatal surface close to the external border. 



The spheno-palatine foramen is constant, and never confluent with 

 the posterior palatine foramen. It varies in shape from oval to round, 

 and may be reduced to the size of the posterior palatine opening. In 

 one specimen its upper edge was wanting. 



The fissure leading upward from the spheno-palatine foramen and 

 separating the ethmoidal and the sphenoidal process is very rarely 

 absent. In one specimen a foramen was observed in the ethmoidal 

 process above the spheno-palatine foramen. 



HUMAN PALATINE BONES. 



The base of the human skull is so greatly compressed along antero- 

 posterior lines that the pterygoid processes almost touch the maxillary 

 tuberosities, only small wedge-shaped pyramidal processes of the pala- 

 tines intervening (Fig. 258). The horizontal plates of the palatines 

 are reduced to narrow strips which do not project backward to form 

 the lateral inferior margins of the posterior nares. 



On the side of the skull (Fig. 260) this compression is most clearly 

 shown in the region of the zygomatic fossa, namely, the space between 

 the temporal, the malar, the maxillary, and the sphenoid, where the 

 lateral part of the sphenoid and the posterior part of the maxillary 

 are almost in contact. They are separated, however, by a vertical slit, 

 in the bottom of which, forming an inner wall, is part of the outer 

 surface of the high and narrow palatine. 



The ventral part of this slit is known as the ptery go -maxillary 



