142 THE MUSCLES. 



These three divisions unite just craniad of the first rib with 

 each other and with the cervical portion of the muscle (_/") 

 (part of scalenus anterior). This consists of a number of 

 small bundles of fibres which arise from the first rib and the 

 transverse processes of the first thoracic and the last six cervical 

 vertebrae. 



The insertion is onto the transverse processes of all the cervi- 

 cal vertebrae, including the axis and atlas. According to Strauss- 

 Durckheim the fibres from any given transverse process are insert- 

 ed into the transverse processes of all the vertebras craniad of it. 



The muscle is partly continuous craniad with the longus 

 capitis (e~). The cervical nerves pass out between the bundles 

 of the cervical portion. 



Relations. Outer (lateral) surface in the thoracic region 

 with the external oblique (Fig. 68, /), the pectoralis minor 

 (Fig. 65, <?), and in part with the serratus anterior (Fig. 73, i)\ 

 in the cervical region with the sternomastoid (Fig. 65, g). 

 Inner (medial) surface with the serratus anterior (Fig. 73, z), 

 the levator scapulae (Fig. 73, //), the longus atlantis, the trans- 

 verse processes of the cervical vertebrae, and tfre longus capitis 

 (Fig. 73, e). 



Action. Flexes the neck and draws the ribs craniad. 



M. longus capitis (or rectus capitis anterior major) (Fig. 

 72, #; Fig. 73, e). This is a long muscle lying on the ventral 

 aspect of the cervical vertebrae. With the muscle of the 

 opposite side and the underlying longus colli (Fig. 72, g'} it 

 forms a trough in which lie the oesophagus, pharynx, and 

 trachea. 



Origin by five (or six) heads from the ventral margins of 

 the transverse processes of the cervical vertebrae from the 

 second to the sixth inclusive. The heads unite into a common 

 belly, the lateral border of which is united with the levator 

 scapulae ventralis (Fig. 72, c'') near its insertion. 



Insertion into the body of the sphenoid bone between the 

 bulla and the middle line. The insertion extends craniad 

 onto the basisphenoid. 



Relations. Ventral surface with the sternomastoid (Fig. 

 65 , g) and the large lymphatic gland ventrad of the external 



