82 DR. BEALE, ON THE TISSUES. 



In the next preparation, ganglion cells and large bundles 

 of gray, gelatinous, nerve fibres are seen. These have been 

 dissected off from the pericardium of the ox. Three sepa- 

 rate ganglion cells situated at the side of the nerve fibre have 

 been placed in the field, and each ganglion cell is surrounded 

 with bands of nerve fibres resembling those of which the 

 trunk of the nerve is composed. Nuclei exactly resembling 

 those in the fibres are seen embedded in the substance of the 

 ganglion. 



From this and other appearances one cannot but conclude 

 that the fibres are continuous with the ganglion cells, and 

 are developed from them. The nuclei being formed in the 

 substance of the ganglion cell, as well as subsequently by the 

 division of those connected with the fibres. Dr. Beale believes 

 that the nerve fibre with its nuclei may be regarded almost 

 as an extended ganglion cell. Each ganglion cell is connected 

 vrith several nerve fibres, and the so-called capsule of these cells, 

 generally described as consisting of areolar tissue, is really 

 composed of nerve fibres which wind round a considerable part 

 of the circumference of the cell, and then divide into bundles, 

 which pass in different directions. The nuclei which are 

 described as the nuclei of the areolar tissue capsule are the 

 nuclei of the fibres and exactly resemble those in unquestion- 

 able nerve fibres. Those nerve fibres embedded in the sub- 

 stance of the pericardium seem to contain no tubular or dark 

 bordered nerve fibres (fibres with the white substance of 

 Schwann) . 



On the external portion of these bundles of nerve fibres in 

 the adult and surrounding the ganglia, a considerable quantity 

 of areolar or connective tissue generally exists, and very 

 commonly the quantity is so great that the nerve fibres and 

 ganglia are obscured by it. A microscopic ganglion embedded 

 in the areolar tissue, just outside the base of the aorta near 

 its origin, from the human subject was shown, and a ganglion 

 embedded in the adipose tissue from the left ventricle of the 

 heart of the pig was also exhibited. The ganglia are nume- 

 rous in the grooves between the auricles and ventricles in the 

 pig's heart, but they are so completely embedded in the 

 adipose tissue that it is only by making thin sections one 

 after the other that they can be discovered. Numerous 

 microscopic ganglia have also been found in corresponding 

 situations in the human heart. 



These preparations prove that the pericardium contains 

 numerous very fine bundles of nerve fibres which form a 

 network situated at the deep aspect of the fibrous pericar- 

 dium, and on the surface of the muscular fibres. The 

 branches are much more numerous in and near the longitu- 



