THE CRANIAL NERVES 293 



nerves are stimulated there is an increased production of sugar 

 even to the point of glycosuria. The irritation is probably re- 

 flected through the sympathetic; indeed it is not supposed that 

 the vagi are concerned in the glycogenic function of the liver, ex- 

 cept reflexly; its section only prevents the conduction cephalad of 

 the impressions which usually give rise to a secretion of glycogen. 

 The connection of the vagus with the kidneys, spleen and 

 suprarenal capsules is obscure. 



Eleventh Nerve (Spinal Accessory). 



Origin. This nerve consists of a cranial portion, accessory 

 to the tenth, and a spinal portion. The apparent origin of the 

 cranial root is from the side of the medulla just below the vagus. 

 Its deep origin is in the medulla to the posterior and outer side 

 of the nucleus of the ninth. The apparent origin of the spinal 

 portion is by several filaments from the side of the cord as low 

 down as the sixth cervical nerve. Its deep origin is from a 

 column of cells in the anterior cornu of gray matter of the cord. 



Course and Distribution (Accessory Portion). Passing out to 

 the jugular foramen it is joined by the spinal portion, and sends 

 a few filaments to the ganglion of the root of the tenth; then 

 leaving the spinal portion it finds exit from the cranium by the 

 jugular foramen, passes over the ganglion of the trunk of the 

 tenth (adherent to it), and is, continued chiefly in the pharyngeal 

 and superior laryngeal branches of that nerve (Gray), but in the 

 recurrent laryngeal as well. 



Spinal Portion. Running upward between the two roots of 

 the spinal nerves the spinal portion enters the cranial cavity by 

 the foramen magnum, passes outward to the jugular foramen, 

 where it joins the accessory portion to separate from it on pass- 

 ing through that foramen. After leaving the skull it takes a 

 course backward, pierces the sterno-mastoid, crosses the occipital 

 triangle and terminates in the trapezius. It gives branches to 

 the sterno-mastoid and to the cervical plexus. 



