BONES OP THE FACE. 203 



antrum, and, though the largest of all the bones of the face, 

 is nevertheless exceedingly light, on account of the great 

 size of the antrum. 



Its development is not agreed on among anatomists. Six 

 centres of ossification are enumerated, viz: one for the 

 body and one for each of the processes, nasal, malar and 

 palate, and two for the alveoli. Ossification, however, 

 begins very early, about the end of the first or beginning 

 of the second month of fcetal life, in the alveolar arch. 

 The anterior palatine portion remains distinct for two or 

 three years, and is called the os-incisivum or inter-maxillary, 

 and represents the permanent condition in some of the in- 

 ferior animals. At birth this bone has great transverse 

 breadth, but little height, owing to the floor of the orbit 



and the alveolar arch coming so close together, which is, 



however, gradually remedied by the enlargement of the 



antrum or maxillary sinus. 



Its articulations are with two of the cranium, the frontal 



and ethmoid, and seven of the face, viz: the palate, the 



malar, nasal, lachrymal, inferior turbinated, vomer and 



its fellow. 



Palate Bones (ossa 



palati.) The situation of 



the palate bones is at 



the posterior part of the 



nares. They contribute to 



form the floor of the or- 

 bit, the side of the nose, 



and the palate. They are 



symmetrical. The/bra is 



irregular, though it has 



FIG. 45, A represents a posterior view of the Palate Bone, a Nasal surface 

 horizontal plate. 6 Nasal surface of ascending plate, d Articulating 

 border for its fellow, c, fc, I Pterygoid process. / Process formed by junc- 

 tion with its fellow, g Horizontal articulating ridge for inferior turbinated 

 bone, h Spheno palatine foramen, t Orbital process, j Sphenoidal process. 



FIG. 45, B represents ascending plate of Palate Bone, on its spheno-maxil- 

 lary surface, a Articulating surface with superior maxillary bone. 6 Poste- 

 rior palatine canal, c Spheno-palatine foramen, d Spheno-maxillary face. 

 t Orbital face. /Maxillary face, g Sphenoidal process, h Pterygoid process. 



