The  nerve  supply  of  the  larynx  is  received  from  the  superior  and
inferior  or  recurrent  laryngeal  nerves,  branches  of  the  vagus.  Sen-
sory fibers  from  the  superior  laryngeal  branch  furnish  acute  sensi-
bility to  the  glottis.  These  fibers  carry  impressions  to  the  medulla
oblongata  while  motor  impulses  are  transmitted  by  the  inferior  laryn-
geal. By  this  mechanism,  foreign  bodies  and  irritating  gases  are
prevented  from  gaining  entrance  to  the  lungs  by  closure  of  the  glottis.
The  inferior  laryngeal  is  supposed  to  supply  motor  impulses  to  all
the  muscles  with  the  exception  of  the  crico-thyroid,  which  receives
motor  impulses  from  the  superior  laryngeal.  The  inferior  recurrent
laryngeal  nerve  contains  both  adductor  and  abductor  fibers.  The
adductor  fibers  are  presumed  to  be  stronger  than  the  abductor  fibers.
The  arterial  blood  supply  is  derived  from  the  superior  and  inferior
thyroid  arteries.  "The  venous  supply  empties  into  the  superior
thyroid  veins.  The  capillaries  are  very  fine  and  lie  directly  beneath


72  DISEASES   OF   EAR,   NOSE  AND  THROAT.
the  epithelium. "  The  lymphatic  network  is  situated  beneath  the  cap-
illaries.
