704 THE SYMPATHETIC NERVES. 



anterior margin of the levator ani muscle the cavernous nerves are joined 

 by some short filaments from the pudic nerve. After distributing twigs to 

 the forepart of the prostate, these nerves divide into branches for the erectile 

 substance of the penis, as follows : 



Small cavernous nerves (Mtiller), which perforate the fibrous covering of 

 the corpus cavernosum near the root of the penis, and end in the erectile 

 substance. 



The large cavernous nerve, which extends forward on the dorsum of the 

 penis, and dividing, gives filaments that penetrate the corpus cavernosum, 

 and pass with or near the cavernous artery (art. profunda penis). As it 

 continues onwards, this nerve joins with the dorsal branch of the pudic 

 nerve about the middle of the penis, and is distributed to the corpus 

 cavernosum. Branches from, the foregoing nerves reach the corpus spongi- 

 osum urethrse. (Miiller, " Ueber die organischen Nerven der erectilen 

 marinlichen Geschlechtsorgane," <fec. Berlin, 1836.) 



NERVES OF THE OVARY. The ovary is supplied chiefly from the plexus 

 prolonged on the ovarian artery from the abdomen ; but it receives another 

 offset from the uterine nerves. 



VAGINAL PLEXUS. The nerves furnished to the vagina leave the lower 

 part of the pelvic plexus that part with which the spinal nerves are more 

 particularly combined. They are distributed to the vagina without pre- 

 viously entering into a plexiform arrangement ; and they end in the erectile 

 tissue on the lower and anterior part, and in the mucous membrane. 



NERVES OF THE UTERUS. These nerves are given more immediately 

 from the lateral fasciculus prolonged to the pelvic plexus from the hypo- 

 gastric plexus, above the point of connection with the sacral nerves. 

 Separating opposite the neck of the uterus, they are directed upwards with 

 the blood-vessels along the side of this organ, between the layers of its 

 broad ligament. Some very slender filaments form round the arteries a 

 plexus, in which minute ganglia are found scattered at intervals, and these 

 nerves continue their course in the substance of the organ in connection 

 with the blood-vessels. But the larger part of the nerves soon leave the 

 vessels ; and after dividing repeatedly, without communicating with each 

 other and without forming any gangliform enlargements, sink into the sub- 

 stance of the uterus, penetrating for the most part its neck and the lower 

 part of its body. One branch, continued directly from the common hypo- 

 gastric plexus, reaches the body of the uterus above the rest ; and a nerve 

 from the same source ascends to the Fallopian tube. Lastly, the ftindus of 

 the uterus often receives a branch from the ovarian nerve. (Fr. Tiede- 

 mann, Tab. Nerv. Uteri, Heidelberg, 1822 ; Robert Lee, in Phil. Trans., 

 1841, 1842, 1846, and 1849; and Snow Beck, in Phil. Trans., 1846, 

 part ii.) 



The nerves of the gravid uterus have been frequently investigated, 

 with a view to discover if they become enlarged along with the increase 

 in size of the organ. It is ascertained that the increase which takes place 

 is confined, for the most part, to thickening of the fibrous envelopes of 

 the nerves ; but it appears also, from the researches of Kilian, that fibres 

 furnished with a medullary sheath, which in the unimpregnated state of the 

 uterus lose that sheath as they proceed to their distribution, in the im- 

 pregnated condition of the uterus continue to be surrounded with it as 

 they run between the muscular fibres. (Farre, in Supplement of Cyclopaedia 

 of Anat. and Phys., " Uterus and Appendages.") 



