THE SYMPATHETIC NERVE SYSTEM 385 



portion of the cord and distributes branches to the 

 bladder, rectum, organs of reproduction, etc. 



There are other ganglia situated in the bony cavities 

 of the face and skull, and portions of the neck and 

 face, which, on the one hand, are in intimate relation 

 with the cerebrospinal system through branches of 

 communication received from the cranial nerves, and, 

 on the other hand, .give off branches of distribution 

 to the salivary glands, organs of special sense, particu- 



FIG. 138 



INTERNAL BRANCH 



EXTERNAL BRANCH 



^POSTERIOR PRIMARY 

 DIVISION 



ANTERIOR PRIMARY 

 DIVISION 



Plan of the constitution of a spinal nerve. (W. Keiller, in Gerrish's 

 Text-book of Anatomy.) 



larly nerves from the ciliary ganglion which controls 

 the regulation of the pupil in regard to the admission 

 of light to the retina. 



The Connections of the Sympathetic Ganglia with 

 the Spinal Nerves. The spinal nerves as they leave 

 the foramen between the vertebra are connected to 

 the ganglia by two small nerves called the rami com- 

 municantes. One branch is white, the other gray. 

 The white rami are found connecting only the spinal 

 nerves included between the first thoracic nerve and 

 the second or third lumbar and the corresponding 

 ganglia. The gray rami are found passing from each 

 one of the ganglia to the corresponding spinal nerve. 

 25 



