ON THE GANGLIONS AND SYMPATHETIC NERVES. 505 



been much neglected by anatomists, who, considering the gan- 

 glions as plexuses more condensed, have regarded it only as 

 destined to separate or to unite the nervous filaments (Scarpa), 

 or to perform the functions of the cellular tissue (Haase). 

 The matter which surrounds the medullary filaments of the 

 ganglions is a particular cellular tissue, the interstices of which 

 are filled with a mucilaginous or gelatinous pulp, of a reddish 

 ash colour, yellowish in some ganglions. This colour, like 

 that of other organs, does not depend solely on the quantity 

 of blood which they receive. 



This secondary substance is not equally abundant, and is not 

 altogether united to the medullary substance in the same man- 

 ner in all the ganglions. 



799. Scarpa says that this pulpy matter is fatty in very fat 

 subjects. Meckel appears to be of the same opinion. Bichat 

 thinks, on the contrary, that the ganglions are never trans- 

 formed into fat. The observations of Wutzer, and my own, 

 are entirely in union with those of Bichat. In very fat sub- 

 jects, there accumulates, under the 'membrane of the gangli- 

 ons, fat, which, when in great quantity, surrounds not only 

 the ganglion, but compresses it and diminishes its size; not- 

 withstanding it is itself never changed into fat. 



800. The ganglions are enveloped by a cellular or fibrous 

 membrane, which differs in the different kinds of ganglions. 



801. The blood-vessels of the ganglions are very numer- 

 ous. The arteries come from the neighbouring trunks; they 

 ramify first in the membrane, where they form a net-work; 

 delicate branches penetrate into the filamentous and pulpy 

 tissue of the ganglion; sometimes arterial branches penetrate 

 into the ganglion with the nervous filaments, and accompany 

 them. The veins offer a similar distribution. Nothing is 

 known concerning the tymphatic vessels of these organs. 



802. The medullary filaments present no interruption in 

 the ganglions; they establish a continuity or an uninterrupted 

 connexion between the nervous cords, in the course of which 

 the ganglions are placed. These medullary filaments form 

 connexions in the interior of the ganglion, and traverse them 

 in different directions, in such a manner as to unite together all 



