ON THE ORGANIC FUNCTIONS. 863 



our being thereby led to regard the processes in question as <l<'i>ni<!< nt upon 

 Nervous agency, a doctrine for which there seems no valid foundation. 

 Throughout the animal body, it may be observed that, the more Vegetative 

 the nature of any function, the less is it under the influence of the Nervous 

 System, save where that influence is required to bring it into harmony with 

 other functions, sometimes by exciting, sometimes by checking, and some- 

 times by otherwise modifying them, very much in the way that a rider 

 guides and controls the movements of his horse. It is evident that this in- 

 fluence must be principally exerted through the Sympathetic or Visceral sys- 

 tem of nerves, since a large proportion of the organs on which it operates 

 are supplied by no other; and hence this apparatus has been commonly 

 designated the "Nervous system of organic life," as distinguishing it from 

 the Cerebro-spinal system, which is the " Nervous system of animal life." 

 There is, however, no such parallelism between them as this designation 

 would imply ; for whilst the operations of the Cerebro-Spinal system essen- 

 tialli/ constitute the Animal life of the individual, those of the Sympathetic 

 cannot be fairly said to do more than control and direct those of Nutrition 

 and Secretion. We shall now inquire into the structure and relations of the 

 Sympathetic System ; and shall then examine the nature of the actions 

 which there seems reason to attribute to it. 



711. Sympathetic Nervous System. That collection of scattered but mutu- 

 ally connected ganglia and nerves, of which this apparatus is made up, may 

 be ranged under the following groups: 1. The isolated ganglia and nerves 

 in immediate connection with the Viscera, which seem to be the chief cen- 

 tres of the system ; these form three principal plexuses, the Cardiac, the 

 Solar, and the Hypo gastric. 2. The double chain of Prevertebral ganglia, 

 with connecting cords, which lies in front of the Vertebral column, and 

 which communicates on the one hand with the Spinal nerves, and on the 

 other with the before-named plexuses. Under this head we should probably 

 rank the minute Cranial ganglia, which are situated in the neighborhood of 

 the Organs of Sense, and in immediate connection with the branches of the 

 Fifth pair that proceed to them ; these are the ophthalmic, otic, spheno pala- 

 tine, and sub maxillary ganglia. 3. The ganglia on the posterior roots of the 

 Spinal nerves ; under which head we are probably to rank not only the 

 Gasserian ganglion of the Fifth pair, but also the ganglia near the roots of 

 the Pueumogastric and Glosso-pharyngeal nerves. The trunks of the Sym- 

 pathetic are made up of different orders of fibres; some of these having 

 their central termination in the vesicular matter of the Sympathetic ganglia 

 themselves, whilst others are derived from the Cerebro-spinal system. The 

 former, which are all of the "gelatinous kind," 1 are most abundant in the 

 great Visceral plexuses; but they may be traced from the prevertebral ganglia 

 into the Spinal nerves, part of them proceeding to the ganglia on their pos- 

 terior roots (whence fibres are given off that mingle with their spinal fibres), 

 whilst other parts enter the anterior roots and mingle with their fibres. On 

 the other hand, the latter, which are of the "tubular" kind, are derived by 

 the same cords of communication (these being commonly termed the " roots" 

 of the Sympathetic, but being really commissural bands that bring the two 

 systems into connection) from both roots of the Spinal nerves, and pass 

 through the prevertebral ganglia into the Sympathetic system, without un- 

 dergoing any ostensible change. Thus it appears that the Cerebro-spinal and 



1 It. must be carefully borne in mind, that, although the proper Sympathetic fibres 

 are all "gelatinous," yet that the Cerebro-Spinal system contains "gelatinous" 

 fibres of its own, which are very abundant in some parts. An account of Kuttner's 

 and lleinak's views on the structural relations of the prevertebral ganglia, will be 

 found in the JVIedico-Chirurgical Review, 1868. 



