THE SPIRAL NER VES 



1015 



The Muscular Branches (Fig. 747) are distributed to the Stvloglossus. Hyo- 

 glossus, Geniohyoid, and Geniohyoglossus muscles and to the Chondroglossus. 

 when present. At the under surface of the tongue numerous slender branches 

 (rami linguales) pass upward into the substance of the organ to supply its In- 

 trinsic muscles. 



Hypo-glotsal nerve. 

 Pneumogastric nerve. 

 Olosso-pharyngeal nerve 



FIG. 748. Hypoglossal nerve, cervical plexus, and their branches. 



Applied Anatomy. A wound in the submaxillary region may injure the hypoglossal nerve 

 and result in motor paralysis of the corresponding half of the tongue. The hypoglossal nerve is 

 an important guide in the operation of ligation of the lingual artery (see p. 594). It runs for- 

 ward on the Hyoglossus muscle just above the great cornu of the hyoid bone, and forms the 

 upper boundary of the triangular space (Lesser's triangle) in which the artery is to be sought for 

 by cutting through the fibres of the Hyoglossus muscle. 



THE SPINAL NERVES (NERVI SPINALES). 



The spinal nerves spring from the spinal cord, and are transmitted through 

 the intervertebral foramina on either side of the spinal column. There are 

 thirty-one pairs of spinal nerves, which are arranged in the following groups, 

 corresponding to the region of the vertebral column through which they pass: 



Cervical 8 pairs. 



Thoracic 12 '" 



Lumbar 5 " 



Sacral 5 " 



Coccygeal 1 pair. 



