EEPOET ON THE SPHENISCIU.E. G3 



3. Splenius capitis. 



Splmius, Vicq d'Azyr, 1773, p. 581, No. 4. 



Petit complexus, Cuvier, vol. i. p. 237. 



Grosser Hahmuskel, Merrem. 



Der hauschdhnliche MmkeJ, Tiedemann, p. 282, No. 2. 



Der Bauschmuskel des Kopfes, Wiedemann, p. 75. 



Grand droit posterieur, Gervais and Alix, p. 1 4. 



Attachments. — The splenius capitis arises from tlie spinous processes of the second 

 and third, and to a less extent from that of the fourth, cervical vertebrae. Its muscular 

 fibres pass forwards, and are inserted into the posterior surface of the transverse occipital 

 crest. 



Action. — This muscle extends the skull upon the vertebral column. 



Relations. — The splenius lies in contact with its fellow of the opposite side. It is 

 crossed superficially from without inwards by the complexus. 



Nerve supply. — A branch from the posterior division of the second cervical nerve. 



Variations. — In Spheniscus demersus this muscle is divisible into two portions, 

 a superficial and a deep, which are separated by a cellular interval. The latter arises 

 from the spine of the third cervical vertebra, and is inserted into the occipital bone 

 under cover of the superficial portion. 



4. Rectus capitis lateralis. 



Les droits lateraux, Viuq d'Azyr, 1773, p. 582, No. G. 

 Seitenbeuger des Kopfs, Wiedemann, p. 75. 

 Seitenbeugcr des Kopfs, Tiedemann, p. 284, No. 6. 

 Droit lateral (1), Cuvier, vol. i p. 237. 

 Trachelo-mastoid, Meckel, vol. vi. p. 13, No. 1. 

 liectus capitis lateralis (?), Owen, p. 30. 

 Trachelo-mastoid, Selenka, vol. vi. p. 99, No. 15. 

 Basi-transversaire (1), Gervais and Alix, p. 15. 



Attachments. — This muscle arises by four fleshy slips from the hyperapophyses of the 

 second, third, fourth, and fifth cervical vertebrse. The fibres converge as they pass 

 forwards, and are inserted by means of a stout tendon into the hollowed surface of the 

 basi-occipital bone, in front of the foramen magnum. 



Action. — The two muscles acting together flex the skull upon the vertebral column. 



Relations. — The muscle arises along with the complexus. As it passes forwards 

 it is crossed superficially by the inferior oblique, and is inserted close to the outer side 

 of the rectus anticus major muscle. 



Nerve supply. — Branches from the posterior divisions of the anterior cervical nerves. 



