SACRAL GANGLIA. 69? 



diminished in size, and gives but few branches to the viscera. Its position 

 on the front of the sacrum is along the inner side of the anterior sacral 

 foramina ; and, like the two series of those foramina, the two cords approach 

 one another in their progress downwards. The upper end of each is con- 

 nected with the last lumbar ganglion by a single or a double iuterganglionic 

 cord ; and at the lower end, they are connected by means of a loop with 

 a single median ganglion, ganglion impar, placed on the fore part of the 

 coccyx. The sacral ganglia are usually five in number ; but the variation 

 both in size and number is more marked in these than in the thoracic 

 or lumbar ganglia. 



Connection with spinal nerves. From the proximity of the sacral ganglia 

 to the spinal nerves at their emergence from the foramina, the com- 

 municating branches are very short : there are usually two for each ganglion, 

 and these are in some cases connected with different sacral nerves. The 

 coccygeal nerve communicates with the last sacral, or the coccygeal ganglion. 



Branches. The branches proceeding from the sacral ganglia are much 

 smaller than those from other ganglia of the cord. They are for the 

 most part expended on the front of the sacrum, and join the corresponding 

 branches from the opposite side. Some filaments from one or two of the 

 first ganglia enter the hypogastric plexus, while others go to form a plexus 

 on the middle sacral artery. From the loop connecting the two cords on 

 which the coccygeal ganglion is formed, filaments are given to the coccyx 

 and the ligaments about it, and to the coccygeal glaud. 



COCCYGEAL GLA.ND. 



Under this name has been described by Luschka a minute structure, 

 which has since received the attention of a number of writers. It is 

 usually, according to Luschka, of the size of a lentil, and sometimes as large 

 as a small pea ; its colour is reddish grey ; its surface lobulated ; and it 

 occupies a hollow at the tip of the coccyx, between the tendons attached to 

 that part. It receives terminal twigs of the middle sacral artery and 

 minute filaments from the ganglion impar. It consists of an aggregation of 

 grains or lobules, which in some instances remain separate one from 

 another. These lobules are principally composed of thick- walled cavities of 

 vesicular and tubular appearance, described by Luschka and subsequent 

 writers as closed follicles filled with cellular contents, but recently demon- 

 strated by Julius Arnold to be clumps of dilated and tortuous small arteries, 

 with thickened muscular and epithelial coats. Nerve-cells are found scattered 

 in the stroma of the organ. 



The coccygeal gland is a structure evidently of a similar nature to the ganglion 

 intercaroticum, the principal differences apparently being, that the glomeruli of the 

 ganglion intercaroticum are produced principally by the convolution and ramification 

 of arterial twigs, while in the coccygeal gland there is dilation of the branches 

 and thickening of their walls ; and that the nervous element 'is more developed 

 in the intercarotid ganglion than in the coccygeal gland. Arnold, with Luschka, 

 appears inclined to consider both structures as allied iu nature to the suprarenal cap- 

 sules. According to Arnold, there is always a number of small grape-like appen- 

 dages on the coccygeal part of the middle sacral artery, microscopic in size, but 

 similar in nature to the lobules of which the coccygeal gland is composed. (Luschka, 

 " Der Hirnanhang und die Steissdruse des Menschen." Berlin, 1860. Also "Anat. 

 d. Menseh./' vol. ii. part 2, p. 187. Julius Arnold in Virchow's " Archiv," March, 

 1865.) 



z z 



