THE MAMJIBLE 



65 



Its six ('cntrcs are mainly named according to their jjosition. 



The mento-Meckelian. — This is deposited in the distal end rif Meckel's 

 (mandibular) cartilage, and gives rise to that portion of the bone Ijetween the 

 symphysis and the mental foramen. 



The dentary. — This forms the lower border and outer plate, and supports the 

 teetli. hence its name. 



Fk;. 7."). — The Mani>ii{i,k at Birth. 



OUTER VIEW 



INNER VIEW 



The coronoid. — This gives rise to the process of that name. 

 The condyloid. — This forms the condyle and adjacent portion of the neck nf 

 the bone. 



The angular. — This gives rise to the angle of the bone. 



The splenial. — This centre appears three weeks later than the portions already 



Fig. 76. — The Skull of ax Old Woman Eighty-three Years Old. to show the 

 Changes in the Mandible and Maxilla. 



mentioned. It forms the inner plate of the mandible from near the symphysis to 

 the mandilnilar foramen. The mandibular spine represents the posterior extremity 

 of the splenial. Its line of junction with the dentary is indicated in the adult bone 

 by the mylo-hyoid groove. 



At birth the mandible is represented bv two nearly horizontal troughs of bone 

 5 



