114 EQUINE ANATOMY. 



10th, or Pneumogastric. 



Snpe7ficial Origin. — Antero-lateral tract of medulla. 

 Deep Origin. — Floor of fourth ventricle. 



Exit. — By posterior lacerated foramen, above carotid artery, to 

 front of thorax, dividing into bronchial and (Esophageal. 



Branches. 



Comnmnicating to eleventh, superior and inferior cervical 

 ganglia. 



Superior laryjtgeal, to mucous membrane of larynx and crico- 

 thyroid muscle. 



Inferior laryngeal, to all muscles of larynx except crico-thyroid. 



Bronchial, to bronchi and lungs. 



(Esophageal, to oesophagus, stomach, liver and solar plexus. 



11th, or Spinal Accessory. 



Sipefficial Origin. — Lateral tract of medulla, along whole 

 cervical region of cord. 



Deep 07-igin. — Fourth ventricle. 



Exit. — Up through foramen magnum and foramen lacerura to 

 neck, and follows mastoideo-humeralis. 



Branches. 



To ce?'vical sympathetic, steimo-maxillaris, mastoideo-humeralis , 

 cervical and dorsal trapezius and cervical nerves. 



12th, or Hypoglossal. 



Supei'ficial Origin. — Side of medulla near inferior spinal roots. 

 Deep Oi'igin. — From fourth ventricle. 

 Exit. — Condyloid foramen. 



Branches. 



To muscles of tongue. 



SPINAL NERVES. 



They are 42 or 43 pairs that leave the spinal canal by the in- 

 tervertebral foramina. The superior or sensory roots have a 

 ganglion developed on them. The uiotor and sensory roots unite 

 and soon after divide into a superior branch to the spinal muscles 

 and integument, and an inferior to the lower part of the trunk 

 and extremities. Their relative number in the different regions 

 are — cervical, 8; dorsal, 18 ^ lumbar, 6; sacral, 5; coccygeal, 6 

 or 7. 



