Chap. V] 



THE SKELETON 



63 



veolar process, and is excavated into cavities, varying in depth 

 and size according to the size of the teeth they contain. The 

 body of the bone is hollowed out into a large cavity known as the 

 antrum of Highmore, which opens into the nose. Abnormal 

 conditions of either the nose or teeth may cause an infection of 

 these antrums. 



Mandible, or lower jaw-bone, also known as inferior maxillary. 

 — It is the largest and strongest bone of the face. At birth, it 



ENTAL 

 PROTUBERANCE 



Fig. 39. — The Mandible. 



Viewed from the right and a little in front. 

 (Gerrish.) 



consists of two lateral halves, which join and form one bone during 

 the first or second year. It serves for the reception of the lower 

 teeth, and undergoes several changes in shape during life, owing 

 mainly (1) to the first and second dentition, (2) to the loss of 

 teeth in the aged, and (3) the subsequent absorption of that part 

 of the bone which contained 

 them. It articulates, by 

 its condyles, with the sock- 

 ets in the temporal bones, 

 which allows for free move- 

 ment in mastication. 



Hyoid bone (os hyoi- 

 deum). — Is an isolated U- 

 shaped bone lying in front 

 of the throat, just above the laryngeal prominence (Adam's 

 apple). It supports the tongue, and gives attachment to some 

 of its numerous muscles. 



Fig. 40. ^- The Hyoid Bone. Viewed from 

 the left and in front. (Gerrish.) 



