134 



THE SKELETON 



lated with the xiphoid process, forming the meso-metasternal joint, the two 

 opposed surfaces being separated by a layer of cartilage so long as they are not 

 united by bone. 



The xiphoid (ensiform) process is the thin, elongated process projecting 

 downward between the cartilages of the seventh ribs. It is the least developed 



Fig. 161. — The Sternum. (Anterior view.) 

 Jugular notch 



Clavicular notch 



For first costal cartilage ] 



Second 



Xiphoid foramen 



Stemo-mastoid 



Manubrium or pre- 

 sternum 



Pectoralis major 



Body or mesostetnum 



Rectus abdominis 



Aponeuroses of abdominal 

 muscles 



Xiphoid or metasternum 



part of the sternum and is subject to many variations in form, being sometimes 

 pointed, broad and thin, occasionally bifid or perforated by a foramen, and some- 

 times bent forward, backward, or deflected to one side. In structure it is carti- 

 laginous in early life, partially ossified in the adult, but in old age it tends to be- 

 come ossified throughout and to fuse with the body. 



The anterior surface of the xiphoid process Rives attachment to a few fibres of the rectus 

 abdominis nuiscle and the chondro-xiphoid ligament, the posterior surface to the sternal fibres 

 of the diaphragm, and the lowest fibres of the transversus thoracis {triangularis sterni), whilst 



