CHAP. 



IV.] 



SPINAL NERVES : MAN. 



135 



67. The same correlation was established in the case of the Jay 

 Garrulus glandarius, but an actual variation in the number of 

 moveable cervical ribs is not recorded in this species (see Fig. 14, 

 I. and II., Fiirbringer's specimens A and D). Furbringer, M., 

 Morph. Jahrb., 1879, v. p. 375. 



w xn xm Cr xn r cr xv st l * xn xm crxivcr xv st> 



Fig. 14. Diagrams of the cervical ribs and brachial plexus in two Jays 

 (Garrulus glandarius) after Furbringer. 



I. Case in which the brachial plexus began from the xith nerve, the cervical 

 ribs of 13th and 14th vertebras being longer than in II, a case in which the xnth is 

 the first nerve contributing to the brachial plexus. Letters as in Fig. 12. 



The measurements of the two specimens here figured were as 

 follows : 



Furbringer, M., Morph. Jahrb., 1879, V. p. 363. 



But though this correlation between the nerves and the ribs is 

 on the whole decided and unequivocal, it should be explicitly 

 stated that it only occurs within certain limits and is not universal, 

 and this statement of correlation is far from covering the whole 

 ground. Furbringer, I. c. p. 387. 



Brachial Plexus. 



»8. Man and other Mammals. By minute dissection of the 

 brachial plexus in fifty-five subjects (32 foetal and 23 adult) 

 Herringham obtained important evidence as to the parts sup- 

 plied by the fibres of the several spinal roots forming the plexus, 

 and as to the considerable variation which occurs in respect of this 

 supply. Of the facts thus arrived at, two examples may be quoted 



