THE NERVOUS SYSTEM. 417 



transparent and pale, and constitute a wide-meshed plexus without any 

 divisions. With respect to the ganglia, which are placed on the n. 

 trigeminus (ganglion ciliare, oticum, sphenopalatinum, linguale, supra- 

 maxillare), I find their structure more to resemble that of the sympa- 

 thetic ganglia, only that they contain a considerable number of larger 

 nerve-cells. The glossopharyngeus, although endowed with motor pro- 

 perties, still, according to Volkmann (Mull. "Arch.," 1840, p. 488), 

 has no fibres which do not pass through one or other of its ganglia. In 

 its roots, which contain numerous fine fibres, there are, according to 

 Bidder (1. c. p. 30), in the Mammalia, not unfrequently, isolated nerve- 

 cells, often placed free upon it, in which, as in similar cells, on the roots 

 of the n. vagus, the giving off of two middle-sized fibres, it is said, may 

 occasionally be readily perceived. The ganglia of the glossopharyngeus 

 present the same conditions as the spinal ganglia, that is to say, the 

 radical fibres simply traverse them, and, within the ganglion, fibres arise 

 from cells, which are for the most part unipolar ; its ultimate ramifica- 

 tion in the tympanic cavity and in the tongue, contains small ganglia, 

 and otherwise corresponds with that of the n. trigeminus (p. major). In 

 Man, all the roots of the n. vagus enter the jugular ganglion, whilst in 

 some of the Mammalia Dog, Cat, Rabbit, according to Remak (in Fro- 

 riep's "Not.," 1837, No. 54), in the Dog and Sheep, according to Volk- 

 mann (Mailer's "Arch.," 1840, p. 491), but not in the Calf, in which 

 nerve-cells occur in the apparently motor root, it has also a primary 

 fasciculus, which has no connection with the ganglion. In the ganglion 

 jugulare and in the intumescentia ganglioformis of the facial nerve, I 

 have not been able to find anything different from the spinal ganglia, 

 only, that the nerve-cells measure occasionally no more than 0-009 of a 

 line, although it is true that there are also a great many as large as 0-03 

 of a line. The ultimate distribution of the nerve exhibits, as Bidder 

 and Volkmann correctly state, a constant kind of separation of thicker 

 and more slender fibres, so that the branches to the oesophagus, heart, 

 and stomach, are composed almost entirely of fine fibres, whilst in those 

 going to the lungs, and in the laryngeus superior, the fine are to the 

 thick fibres as 2 to 1 ; and in the laryngeus inferior and the rami pha~ 

 ryngei, as 1 to 6-10. All these fine fibres are very far from being 

 derived from the sympathetic, as they occur in preponderating quantity 

 even in the roots of the vagus, and are also numerous in the laryngeus 

 superior. Many of them, moreover, may be nothing more than attenu- 

 ated or originally finer ganglion-fibres, as they are termed, arising in the 

 ganglia of the vagus itself, and which likewise I should not refer to the 

 sympathetic. With respect to the terminations of the vagus, reference 

 must be made below to the proper places. The n. accessorius Willisii, 

 although perhaps also in part sensitive, has no nerve-cells, and in its 



27 



