430 



SYMPATHETIC NERVE. 



portion, which are continued forwards along 

 the sides of the rectum, to form the inferior 

 hypogastric plexuses. 



8. Inferior Hypogastric Plexuses. These 

 consist of a right and left plexus, formed in the 

 manner just mentioned : they contain several 

 small ganglia. Filaments are likewise sent to 

 them from the sacral ganglia, as well as from 

 two or three of the sacral nerves. These 

 plexuses are situated upon the sides of the 

 rectum, the plexuses of opposite sides being 

 united by cross branches. From the plexus 

 proceed the following branches. () Some 

 hsemorrhoidal branches : these are termed the 

 inferior haemorrhoidal nerves ; they are very 

 delicate and unite with the superior hemor- 

 rhoidal branches derived from the inferior 

 mesenteric plexus, and go to supply the rec- 

 tum. (6) Vesical plexus . The nerves proceed- 

 ing to this plexus come from the lower and 

 anterior portion of the inferior hypogastric 

 plexus, and pass to the sides and lower part 

 of the bladder. The nerves are most numerous 

 near the neck of the organ, and have several 

 minute ganglia developed upon them. From 

 the neck numerous branches pass upwards on 

 the sides of the bladder, and are chiefly dis- 

 tributed to its muscular coats ; a few, however, 

 may be traced through the muscular to the 

 mucous coat. From the vesical plexus, fila- 

 ments are given off which pass to the vesiculae 

 seminales, around which they form a plexus ; 

 others pass to the vas deferens and ramify 

 around it, communicating on the spermatic 

 cord with the nerves of the spermatic plexus, 

 while a third portion passes to the prostate 

 gland. The branches which pass to the latter 

 are of considerable size, and form connections 

 with the plexus around the vesiculae seminales. 

 Some of the branches sink into the substance 

 of the gland, others are continued forwards 

 to the erectile tissue of the penis, constituting 

 the so-called cavernous nerves, or cavernous 

 plexus. From these branches are distributed 

 to the membranous portion of the urethra. 

 They then continue forwards, passing beneath 

 the arch of the pubis to the root of the penis. 

 By Miiller*, they are divided into nervi caver- 

 nosi minores, and nervus cavernosus major. 

 The former penetrate the crus of the corpus 

 cavernosus penis, and spread out upon the 

 cells of the erectile tissue : the latter runs 

 along the dorsum of the penis between the 

 dorsal artery and vein. About the middle of 

 the penis it divides into a number of branches 

 and forms communications with the dorsal 

 branch of the pudic nerve : some of the 

 branches accompany the dorsal vessels and 

 unite with those of the opposite side ; the 

 greater portion, however, penetrate the corpus 

 cavernosum and are distributed to its sub- 

 stance. 



9. Uterine Plexus. The nerves destined for 

 the supply of the uterus are derived from the 

 upper and posterior part of the inferior hypo- 

 gastric plexus, and also from the superior 



* Ueber die organischen Nerven der erectilen 

 mannlichen Geschlechts-organe. Berlin, 1836. 



plexus of the same name. They pass between 

 the folds of the broad ligament in company 

 with the uterine vessels ; before reaehing the 

 uterus, however, the greater portion of them 

 separate from the vessels, and are distributed 

 to the substance of the neck and body of the 

 organ. The portion derived from the superior 

 hypogastric plexus appears to be chiefly dis- 

 tributed to the fundus of the organ : a fila- 

 ment also passes, according to Dr. Beck*, 

 from the ovarian artery to the fundus 

 of the uterus. Besides the branches above 

 mentioned there are others, according to 

 Dr. Beck, derived also from the hypogastric 

 plexus, which assume a plexiform arrange- 

 ment around the vessels, and are characterised 

 by the presence of several minute ganglia. 



Fis. 280. 



Small ganglion from the posterior wall of the cervix 

 of an impregnated uterus of the Cow. 



MINUTE ANATOMY. The branches of the 

 sympathetic nerve present to the naked eye 

 certain characters which, more or less, dis- 

 tinguish them from the proper cerebro-spinal 

 nerves. They have a dull greyish-white ap- 

 pearance, different from the white shining 

 aspect which characterises the nerves belong- 

 ing to the other class. This appearance is 

 better marked in some parts of the nerve than 

 in others, and is best seen in the branches 

 which accompany the blood-vessels. By 

 Valentin this gray appearance of the sym- 

 pathetic nerves was attributed to the presence 

 of the ganglionic corpuscles : this, however, as 

 Remak observed, cannot be the case, inas- 



* Ou the Nerves of the Uterus. Phil. Trans. 

 1846. 



