THE CBEEBEO-SPINAL SYSTEM OF NERVES. 585 



root is derived from the facial through the great superficial 

 petrosal nerve; its sympathetic root from the carotid plexus. 

 Both together constitute the vidian nerve. It would seem that 

 afferent impulses from the nasal chambers pass through this 

 ganglion. The efferent paths are : 1. Motor to the levator pa- 

 lati and azygos uvulae. 2. Vaso-motor, derived from the sym- 

 pathetic. 3. Secretory to the glands of the cheek, etc. 



III. The Otic Ganglion. —Its roots are : 1. Motor, from the 

 third division. 2. Sensory, from the inferior division of the 

 fifth. 3. Sympathetic, from the plexus around the meningeal 

 artery. It makes communication with the chorda tympani and 

 seventh, and supplies the parotid gland with some fine fila- 

 ments. Motor fibers mixed with sensory ones pass to the tensor 

 tympani and tensor palati. 



IV. The Submaxillary Ganglion. — Its roots are: 1. Branch- 

 es of the chorda tympani, from which pass (a) secretory fibers to 

 the submaxillary and sublingual glands, (6) vaso-motor (dilator) 

 fibers to the vessels of the same glands. 2. The sympathetic, 

 derived from the superior cervical ganglion, passing to the sub- 

 maxillary gland. It is also thought to be the path of vaso-con- 

 strictor fibers to the gland. 3. The sensory, from the lingual 

 nerve, supplying the gland substance, its ducts, etc. 



Pathological. — 1. The motor division of the nerve, when 

 the medium of efferent impulses, owing to central disorder, may 

 cause trismus (locked-jaw) from tonic tetanic action of the mus- 

 cles of mastication supplied by this nerve. 2. Paralysis of the 

 same muscles may ensue from degeneration of the motor nuclei 

 or pressure on the nerve in its course. 3. Neuralgia of any of 

 the sensory branches may occur from a great variety of causes, 

 and often maps out very exactly the course and distribution of 

 the branches of the nerve. 4. Vaso-motor disturbances are not 

 infrequently associated with neuralgia. Blushing is an evi- 

 dence of the normal action of the vaso motor fibers of the fifth 

 nerve. 5. A variety of trophic (metabolic) disturbances may 

 arise from disorder of this nerve, its nuclei of origin or its gan- 

 glia, such as grayness apd loss of hair (imperfect nutrition), 

 eruptions of the skin along the course of the nerves, etc. Atro- 

 phy of the face, on one or both sides, gradual and progressive, 

 may occur. Such affections as well as others, point in the most 

 forcible manner to the infiuence of the nervous system over the 

 metabolism of the body. 



The Glosso-pharyngeal or Ninth Nerve.— This nerve, to- 



