GAXGLIA. 



cxli 



Fig. LXXX. 



cell-matter or protoplasm is very scanty, and accidentally detached in exami- 

 nation. These nucleus-like bodies are very abun- 

 dant in the superficial grey matter of the cere- 

 bellum. 



In the grey matter of the cerebro-spinal centre, 

 the nerve-cells appear as if imbedded in a sort 

 of matrix of granular substance, interposed be- 

 tween them in greater or less quantity, and 

 very generally traversed by nerve-fibres. But 

 it is very probable that the appearance of gra- 

 nular or molecular matter results from a con- 

 fused interlacement of very fine fibrils, and 

 especially of the fine ramifications of nerve- 

 cells ; or from the crushing and breaking down 

 of such fibres in the process of examination. 

 In the ganglia properly so called, the cells are 

 packed up among nerve- fibres, but each cell is 

 also immediately surrounded by an inclosing 

 capsule (fig. LXXXII. and LXXXIII.). 



The proper nervous substance of the brain 

 and spinal cord is described by Kolliker as being 

 traversed in all directions and supported by a 

 framework of connective tissue the " reti- 

 form " connective tissue described at page Ixxix. This is formed of an inter- 

 union of ramified connective tissue corpuscles, or 

 of a network of fine fibres alone, originally pro- 

 ceeding from such corpuscles. Kolliker names this 

 supporting structure the reticulum of the nervous 

 centres (fig. LXXXL). Virchow proposes the term 

 neuroglia. It is not merely an open mesh-work, 

 but consists also of fine laminae formed of a close 

 interlacement of the finest fibrils, disposed as mem- 

 branous partitions and tubular compartments for 

 separating and inclosing the nervous bundles. 



Such being the structural elements of the ner- 

 vous substance, we have next to consider the ar- 

 rangement of these cells and fibres in the ganglia 

 and nerves which they contribute to form ; the 

 intimate structure of the eucephalon and spinal cord 

 being treated of in the part of this work which is 

 devoted to special or descriptive anatomy. 



Fig. LXXX. SMALL NERVE- 

 CELLS. 



a, from the (cortical) grey 

 matter of the brain. 6 and c 

 are from the cortical substance 

 of the cerebellum ; b resemble 

 detached cell-nuclei. c are 

 smaller bodies, also like cell- 

 nuclei, densely aggregated 

 (from Hannover, magnified 

 340 diameters). 



Fig. LXXXL 



Fig. LXXXL PART OP 

 TUB RETICULUM FROM 

 THE SPINAL CORD. 

 Open meshes are seen ge- 

 nerally, but at two places 

 the close lamelliform in- 

 terlacements are shown. 

 Magnified 350 diameters 

 (from Kolliker). 



OF THE GANGLIA. 



The bodies so named are found in the following situations viz. : 1. On 

 the posterior root of each of the spinal nerves, on one, and probably the 

 corresponding root of the fifth nerve of the encephalon, and on the seventh 

 pair, glosso-pharyngeal and pneumogastric nerves, involving a greater or less 

 amount of their fibres ; also on the branches of certain cerebro-spinal 

 nerves. 2. Belonging to the sympathetic nerve, (a) In a series along 

 each side of the vertebral column, connected by nervous cords, and con- 

 stituting what was once considered as the trunk of the sympathetic. 

 (6) On branches of the sympathetic ; occurring numerously in the abdomen, 

 thorax, neck, and head ; generally in the midst of plexuses, or at the point 



