352 CEREBRO -SPINAL NERVES. 



The larynx, pharynx, and soft palate. The crico-thyroid muscle is supplied by 

 the external laryngeal branch of the pneumo-gastric nerve, and the other intrinsic 

 muscles of the larynx by the recurrent laryngeal. The constrictors of the pharynx 

 are supplied mainly by the bulbar part of the spinal accessory nerve through the 

 pharyngeal branch of the vagus and the pharyngeal plexus ; and the levator palati, 

 azygos uvulse, palato-pharyngeus, and palato-glossus are innervated from the same 

 source. The stylo-pharyngeus, and possibly the middle constrictor in part, are 

 supplied by the glosso-pharyngeal. The tensor palati is supplied through the otic 

 ganglion by the inferior maxillary division of the fifth nerve (and the tensor tympaui 

 is supplied in the same way). 



2. To muscles belonging exclusively to the trunk, and muscles 

 ascending to the skull. All those muscles of the hack which act upon the spine 

 and head, viz., the splenius, complexus, erector spinae, and the muscles more deeply 

 placed, receive their supply from the posterior divisions of the spinal nerves. 



The sterno-mastoid is supplied by the spinal accessory nerve and a twig of the 

 cervical plexus coming from the second cervical nerve. 



The rectus capitis anticus minor and rectus capitis lateralis are supplied by the 

 first cervical nerve, the rectus capitis anticus major by the upper four cervical nerves ; 

 the longus colli and seal-mi receive twigs from nearly all the cervical nerves. 



The muscles of the chest-ivall, viz., the intercostals, subcostals, levatores 

 costarum, serrati postici, and triangularis sterni, are supplied by the intercostal 

 nerves. 



The obliqui, transver sails, and rectus of the abdomen are supplied by the lower 

 six to eight intercostal nerves ; and the internal oblique and transverse muscles also 

 get branches from the first lumbar nerve. The cremaster muscle is supplied by the 

 genital branch of the genito-crural nerve (1, 2 I). 



The quadratus lumhorum receives small branches from the last dorsal and upper 

 one or two lumbar nerves. 



The diaphragm receives the phrenic nerves from the fourth and fifth cervical 

 nerves, branches from the lower intercostal nerves, and likewise sympathetic filaments 

 from the plexuses round the phrenic arteries. 



The muscles of the urethra and. penis are supplied by the pudic nerve (2, 3, 4 s), 

 the levator and sphincter ani by the pudic and the fourth sacral nerves ; and the 

 coccygeus muscle by the fourth and fifth sacral nerves. 



3. To muscles attaching the upper limb to the trunk. The trapezius and 

 the cleido-mastoid receive the distribution of the spinal accessory nerve, and, in union 

 with it, offsets from the cervical plexus. 



The latissimus dor si receives the long subscapular nerve (7, 8 c). 



The rhomhoidei are supplied by a branch from the fifth cervical nerve. 



The levator anguli scapulae is supplied by branches from the third and fourth 

 cervical nerves, and partly also by the branch to the rhomboid muscles. 



The serratus magnus has a special nerve, the posterior thoracic, derived from 

 the fifth, sixth, and usually the seventh cervical nerves. 



The subctavius receives a branch from the place of union of the fifth and sixth 

 cervical nerves. 



The pectorales are supplied by the anterior thoracic branches of the brachial 

 plexus, the larger muscle usually receiving fibres from the lower four cervical and 

 first dorsal nerves, and the smaller from the last two cervical and first dorsal. 



4. To muscles of the upper limb. Muscles of the shoulder. The supra- 

 spinatus and infraspinatus are supplied by the suprascapular nerve (5, G c) ; the 

 subscapularis by the upper and lower subscapular nerves (5, K c) : the teres major 

 by the lower subscapular (5, 6 c) ; and the deltoid and teres minor by the circumflex 

 nerve (5, 6 c). 



