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



pronounced than in the Penguins. To the presence of these cervical curves is attributable 

 the fact that the Penguins, when on terra firma, are able to maintain the peculiarly 

 erect position which every member of the group assumes. The absence of power to 

 produce the flexures in question would, it is evident, render the maintenance of the erect 

 attitude impossible. 



MUSCLES OF THE WING, 

 (rt) Muscles inserted into the Scapula. 



1. Trapezius. 



Trapezdide, Vicq d'Azyr, 1772, p. 630, Xo. L 

 Traphe, Cuvier, vol. i. p. 262. 

 Aufzieher des SchuUerhlattes, p. 154, No. 9. 

 Der Kappenmuskd, "Wiedemann, No. 2, p. 84. 

 Retracteur superficiel, Meckel, vol. vi. p. 22, No. 1. 

 CucitUaris, Schoepss, p. 90, No. 6. 

 Cuadlaris, Selsnka, vol. vi. p. 107, No. 32. 

 Trapeze, Gervais and Alix, p. 21. 



Attachments. — The trapezius arises from the spinous processes of the dorsal vertebrae, 

 from the second to the fifth inclusive, by means of a flat aponeurotic tendon. The 

 fibres pass outwards with a slight obliquity forwards, and are inserted into the anterior 

 half of the vertebral border of the scapula, as well as into the posterior recurved extremity 

 of the clavicle. 



Action. — This muscle approximates the scapula to the vertebral column. In this 

 action it co-operates with the fibres of the rhomboid muscle. 



Relations. — The trapezius is concealed by the anterior portion of the latissimus 

 dorsi. Its deeper surface rests upon the rhomboid muscle. 



Nerve supply. — A special branch from the first cord of the brachial plexus. 



Variations. — In Eudyptes chrysocome from Kerguelen, I found the trapezius arising 

 from the spines of the three anterior dorsal vertebrae, as well as from those of the last two 

 cervical vertebrae. In this bird, as well as in Pygosceles tceniatus and Spheniscus minor, 

 the insertion of the trapezius is confined to the anterior third of the vertebral border of 

 the scapula. 



Remarks. — Gervais and Alix found the trapezius in Eudyptes chrysolopJms 

 attached to the spines of the last two cervical vertebrae, as well as to those of the dorsal 

 vertebrae above mentioned. They do not mention the insertion of this muscle into the 

 recurved extremity of the clavicle. The observations of Meckel and of Schoepss with 

 regard to this muscle in the Penguin agree with my own. 



