THE NERVOUS SYSTEM 179 



forwards inside the tough fibrous sheath surrounding the rectum, 

 and anastomoses with the N. pudendus from the seventeenth spinal 

 nerve. 



The posterior ramus turns caudad, and sends a twig to the M. 

 ilio-caudalis (il.cd.), and then penetrates the sheath to supply the 

 cloacal gland in the male, or the homologous tissue in the female. 



The ventral ramus of N. spinalis ig besides supplying the sub- 

 vertebral muscle also supplies the cloacal gland. 



The remaining spinal nerves, or caudal nerves as they may be 

 termed, show gradual reduction in size and complexity towards the 

 end of the tail, but are not characterized by any other special modifi- 

 cation. 



SYMPATHETIC NERVOUS SYSTEM^ 

 I. Historical. 



Only three papers have been published on the sympathetic ner- 

 vous system of Salamandra. The first, and best known, is by Anders- 

 son (1892). It is somewhat incomplete, but he gives an elaborate 

 figure which illustrates the general relations of the abdominal and 

 caudal portions very well, though the direct connexion he shows with 

 the vagus ganglion must be considered doubtful, while his state- 

 ment that a cranial sympathetic is entirely wanting is without doubt 

 erroneous. The next account, by Jaquet (1900), is obviously based 

 on Andersson's and suffers from the same defects. In 1902 Hoff- 

 mann's paper appeared on the development of the sympathetic 

 system in Salamandra. This work adds several important details to 

 Andersson's account, the most notable of which are the intimate 

 association between the sympathetic nerves and the adrenal bodies 

 (Nebenniere) and the close connexion of the latter with the veins. 

 He denies that the sympathetic chain has any direct connexion with 

 the vagus ganglion, and says that it terminates anteriorly with the 

 ramus communicans to the first spinal nerve. From this point it 

 travels mesialwards along the ventral ramus of this nerve, separates 

 from it again at the point where it leaves the dorsal ramus, and 

 passes forward to the vagus ganglion through the spino-occipital 

 muscles. This certainly misrepresents the facts as far as the adult 

 is concerned, since the anterior continuation of the sympathetic 

 beyond the ramus communicans to the first spinal nerve is easily 

 demonstrable by dissection under the binocular microscope, while 



' It must be noted here that the term 'sympathetic' is used in the anatomicah&ns&,a.nd 

 is not intended to include the system as a whole, which is more correctly called the 

 autonomic nervous system. 



