46 ANATOMY AND PHYSIOLOGY. 



BONES OF THE PELVIS. 



Ossa Innominata. Situated at the sides of the pelvis. Figure, 

 irregular. Each bone is divided into three parts, viz. ilium the 

 uppermost, ischium the lowest, and pubis the anterior. Eminences 

 The crista of the ilium, from which the oblique and transverse 

 muscles of the abdomen arise at its posterior part are two spinous 

 processes, which give adhesion to ligaments at its anterior part 

 are also two spinous processes, the superior gives adhesion to the 

 sartorius, tensor vaginae femoris, and the ligament of the thigh ; 

 the inferior anterior spinous process, about an inch from the former, 

 has arising from it the rectus femoris. The external surface of the 

 iliac portion is covered by the glutsei muscles ; the internal by the 

 internal iliac. Upon the internal surface there is a line even with 

 the pubis ; this is called linea innominata, or rim of the pelvis ; it 

 divides the cavity of the abdomen from the pelvis. Upon the 

 ischiatic portion or ischium are the tuberosity of the ischium, upon 

 which we sit; the spinous process of the ischium, which projects 

 backwards, and gives adhesion to the uppermost sacro-sciatic liga- 

 ment ; the ramus ischii, which joins the pubis. Upon the pubic 

 portion, or pubis, are the body, near the socket, the angles and 

 arches of the pubis. Cavities A notch between the anterior spines 

 of the ilium ; an anterior and posterior ischiatic notch ; the aceta- 

 bulum, which receives the head ef the os femoris, and the foramen 

 thyroideum, or ovale. Each os innominatum is connected with its 

 fellow anteriorly by symphysis, with the sacrum posteriorly by 

 strong cartilages and ligaments, and with the head of the thigh- 

 bone by enarthrosis. Use To form the pelvis ; to retain the gravid 

 uterus in its situation, and to constitute the acetabulum for the 

 thighs. 



Os Sacrum. Situated at the posterior part of the pelvis. 



Os Coccygis. Situated at the apex of the sacrum. 



BONES OF THE SUPERIOR EXTREMITIES. 



The bones of the upper extremities are, on each side, the cla- 

 vicle, scapula, humerus, radius, ulna, bones of the carpus, metacar- 

 pus, and fingers. 



Clavicle. Situated obliquely in fhe upper and lateral parts of 

 the thorax 



Scapula. Situated in the upper and lateral parts of the back. 



Os Humeri. Situated between the scapula and fore-arm. 



Cubit, or Ulna. Situated in the inside of the fore-arm, towards 

 the little finger. 



