734 



THE NERVES. 



5. INFERIOR LARYNGEAL NERVE (Fig. 362, 27, 28). Also named the 

 recurrent, or traclieal recurrent, because of its disposition. It begins in the 

 thoracic cavity and ascends along the trachea to the larynx, all of whose 

 intrinsic muscles it animates, with the exception of the crico-thyroid. 



The two recurrent nerves 



Fig. 341. are not quite symmetrical 



at their origin. That of the 

 right side is detached from 

 the pneumogastric below the 

 axillary artery, nearly at the 

 dorso-cervical arterial trunk. 

 It is immediately reflected 

 forward in embracing the 

 origin of that trunk, which 

 it crosses inwards to be 

 placed against the trachea, 

 in the middle of the prin- 

 cipal cardiac nerves, with 

 some of which it contracts 

 intimate adherences. 



On the left side, it is 

 only when the pneumogas- 

 tric nerve arrives near the 

 root of the lung that it 

 gives off its recurrent. To 

 be reflected forward, the 

 latter turns from left to 

 right behind the arch of 

 the aorta, and arrives be- 

 neath the inferior face of 

 the trachea, among the 

 cardiac nerves, with which 

 it communicates like th| 



DISTRIBUTION OF THE NERVES IN THE LARYNX OF THE right. 



HORSE. The inferior laryngeal 



a, Base of the tongue ; 6, Epiglottis ; c, Arytenoid nerves are in this way 



muscles ; c/, Section of the thyroid cartilage to show mixed at a greater or less 



the parts it covers; e, Cricoid cartilage; /, Trachea; ^ietirirp frrnn their rom- 



0, (Esophagus; A, Thyro-arytenoid muscle; i, Lateral dlstanc om tneu 



crico-arytenoid muscle ; j, Posterior crico-arytenoid mencement, With those sym- 



muscle; k, Arytenoid muscle. 1, Superior laryngeal pathetic nervous branches 



nerve ; 2, Inferior laryngeal ; 3, Branches of the supe- w hich collectively constitute 



nor laryngeal passing to the epiglottis and tongue ; 4, ft ^chea! plexus. They 



Branches of the superior laryngeal passing to the ,. ^ , , J 



oesophagus; 5, Very fine multiple anastomoses between are soon disengaged, hOW- 



the two laryngeals ; 6, Tracheal branches ; 7, Branch ever, and leave the chest, 



to the posterior crico-arytenoid muscle ; a portion is font always in proceedicg 



distributed, through the muscles, to the subjacent a l ong the inferior face of 



mucous membrane ; 10, Branch passing to the arytenoid ,, T- 



muscle; 11, (Esophageal branch of the pharyngeal the trachea, then ascending 



nerve; it sometimes comes from the external laryn- on its Sides, below the ca- 



geal. From^Toussaint's work. rotid arteries, which they 



gradually approach, and 



finally attain the larynx in penetrating beneath the crico-pharyngeal 

 muscle. 



According to Goubaux, the left recurrent must be situated more super- 



