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THE SPIXAL NERVES. 

 SECOND CERVICAL NERVE. 



The anterior division of the second cervical nerve, befjinning between 

 the arches of the first two vertebrae, is directed forwards between their 

 transverse processes, being placed outside the vertebral arterj, and 

 beneath the intertransverse and other muscles fixed to those processes. 

 In front of the intertransverse muscles, the nerve divides into an 

 ascending part, which joins the first cervical nerve, and a descendino- 

 part to the third. * 



if ig. ooi. FJg. 354_ — Diagrammatic 



Outline op the Cer- 

 vicAL AND Brachial 

 Plexuses. (A. T.) i 



The nerves are separated 

 from the spinal cord at 

 their origin and are sup- 

 posed to be viewed from 

 before. CI, is placed op- 

 posite the roots of the first 

 cervical or sub-occipital 

 nei-ve, and the Roman num- 

 bers in succession from II, 

 to VIII, opposite the roots 

 of the corresponding cer- 

 vical nerves ; DI, is placed 

 opposite to the roots of the 

 first dorsal nerve, and II, 

 and III, opposite the second 

 and third nerves ; the origin 

 of the posterior primary 

 branch is shown in all the 

 nerves : of these p 2, indi- 

 cates the great occipital 

 from the second, and p 3, 

 the smallest occijjital nerve 

 from the third. Cervical 

 plexus : 1, anterior primary 

 branch of the first cervical 

 nerve and loop of union with 

 tlie second nerve ; "2, lesser 

 occipital nerve proceeding in 

 this case from the second 

 cervical nerve, more fre- 

 quently from the second and 

 third ; 3, great auricukir 

 nerve from the second and 

 third ; 3', superficial cervical 

 nerve from the third ; 3 n, 

 communicating branches to 

 the descendens noni from 

 the second and third ; 3 s, communicating to the spinal accessory from the second, third, 

 and fourth ; 4, supraclavicular and supra-acromial descending nerves : the loops or 

 arches of communication between the four ujjper cervical nerves, and between tlie fourtii 

 and fifth, are shown ; 4', the phrenic nerve springing from the fourth and fifth nerves. 

 Brachial plexus : V, to VIIl', and D', the five roots of the brachial plexus ; 5, the 

 rhomboid nerve ; 5', suprascapular ; 5", posterior thoracic ; 6, nerve to the subclavius 

 muscle ; 7, 7, inner and outer anterior thoracic nerves ; 8, S', 8", upper and lower sub- 

 scapular nerves. In the larger nerves jjroceeding to the shoulder and arm from the 

 plexus, those of the anterior division are represented of a lighter shade, those belonging 

 to the posterior division darker ; ec, external cutaneous or musculo-cutaneous ; ?«, median ; 

 u, ulnar, ic, internal cutaneous ; w, nerve of AVrisberg ; r, musculo-spiral ; c, circum- 

 flex ; i, intercostal nerves ; i', lateral branch of the same ; iJi, intercosto-humeral nerves. 



t^ec 



