64 THE VOYAGE OF H.M.S. CHALLENGER. 



the integument. They extend from the occiput and the posterior extremity of the 

 lower jaw bone, as far backwards as the junction of the posterior and middle thirds of 

 the neck, where they cease to be distinguishable as a separate muscle. Along the middle 

 line of the neck, inferiorly, this muscle is easily separable from the subjacent panniculus, 

 but above, i.e., along the dorsal middle line of the neck, there is no natural separation 

 between this muscle and the panniculus, the fibres of the two muscles blending with one 

 another. 



Action. — The muscle wrinkles the skin of the neck, and elevates the feathers of that 

 region. 



Relations. — The constrictor colli separates the skin from the subjacent panniculus 

 carnosus. 



Nerve supply. — Branches from various cervical spinal nerves. 



3. Panniculus carnosus. 



Stemo-cervicalis, Owen, p. 23. 



Panniculus carnosus (first portion), Reid, p. 139. 



Peaticier du cou (plan profond), Gervais and Alix, p. 39. 



Attachments.— The panniculus is the great cutaneous muscle of the neck. It arises from 

 the whole of the anterior border of the clavicle below the articulation of that bone with 

 the coracoid. From this origin the fibres diverge, the anterior fibres passing obliquely 

 forwards and upwards, the posterior backwards and upwards, while the intermediate fibres 

 pass with varying obliquities towards the dorsal middle line of the neck. The anterior fibres 

 pass forwards to the occipital bone, into which, as well as into the post-orbital process of 

 the frontal bone, they are inserted. By far the larger number of fibres reach the dorsal 

 middle line of the neck, where they blend with the corresponding fibres of the opposite 

 side, while the posterior fibres, passing obliquely backwards and upwards, blend in a 

 similar manner as far back as the fourth dorsal vertebra. In this way the two muscles 

 of opposite sides form as it were a hood, which covers the cervical as well as the anterior 

 portion of the dorsal region. The lower borders of the two muscles are in contact in front 

 of the clavicle, but as they pass forwards to their insertion into the skull, they diverge so 

 as to leave an angular interval, in which, after removal of the constrictor colli, the trachea 

 and larynx with their muscles are exposed. 



Action. — This muscle wrinkles the skin of the neck, and rufiles the feathers of that 

 region. 



Relations. — The anterior fibres of this muscle are concealed by the constrictor coUi, 

 but the greater portion of the muscle lies immediately underneath the skin. The posterior 

 border of the muscle is free, and extends between the shoulder joints of opposite sides. 

 Its origin is concealed by the anterior fibres of the pectoralis major. 



