THE MUSCLES. 71 



Psoas magnus arises from the bodies and processes of the last 

 dorsal and all the lumbar vertebrae. Inserted into the os femoris, 

 a little below the trochanter minor. Use To bend the thigh for- 

 wards. 



Iliacus inter nus arises from the internal surface of the spine of 

 the ilium. Inserted into the femur in common with the psoas mag- 

 nus. Use To assist the psoas magnus. 



MUSCLES SITUATED ON THE ANTERIOR PART OF THE THORAX. 



Pectoralis major arises from the clavicle, sternum, and seven true 

 ribs. Inserted into the upper and inner part of the humerus. Use 

 To draw the arm forwards, or obliquely forwards. 



Subclavius arises from the cartilage of the first rib. Inserted into 

 the under surface of the clavicle. Use To move the clavicle down- 

 wards. 



Pectoralis minor arises from the third, fourth, and fifth ribs. In- 

 serted into the coracoid process of the scapula. Use To roll the 

 scapula. 



Serratus major anticus arises from the eight superior ribs. In- 

 serted into the basis of the scapula. Use To bring the scapula 

 forwards. 



MUSCLES SITUATED BETWEEN THE RIBS AND WITHIN THE THORAX. 



Inter cost ales externi arises from the lower edge of each upper rib. 

 Inserted into the superior edge of each lower rib. Use To elevate 

 the ribs. 



Intercostales interni, like the former, the fibres are directed from 

 behind forwards. 



Triangularis arises from the middle and inferior part of the 

 sternum. Inserted into the cartilages of the five last true ribs. 

 Use To depress the cartilages of the ribs. 



MUSCLES SITUATED ON THE ANTERIOR PART OF THE NECK, CLOSE 

 TO THE VERTEBRA. 



Longus colli arises from the bodies of the three upper dorsal and 

 transverse processes of the four last cervical. Inserted into the 

 anterior tubercle of the dentatus. Use To pull the neck to one 

 side. 



Rectus internus capitis major arises from the transverse processes 

 of the five last cervical vertebrse. Inserted into the cuneiform pro- 

 cess of the os occipitis. Use To bend the head forwards. 



Rectus internus capitis minor arises from the fore part of the atlas. 



