THE PERIPHERAL NERVOUS SYSTEM OF THE BONY FISHES. 
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The following piiragraplis give the components of the several cranial nerves as I 
have found them in Afenidia, together with a few items concerning tlieir distribution. 
JCII nerve . — This nerve is represented in the first member of the first spinal com- 
plex. It supplies the post-hyal ventral somatic musculature. The pre-hyal somatic 
musculature is not present in the teleosts, the so-called m. genio-hyoideus not being 
homologous with the muscle of that name in the other vertebrates. 
AT nerne . — The spinal accessory nerve can be positively identified, going out 
with the vagus and innervating the trapezius muscle. It probably arises from the 
nucleus ambiguus and is viscero-moto]' in nature. 
A' nerve . — This nerve contains visceromotor, viscero-sensory (communis), general 
cutaneous and lateral line fibers. The two first types mahe up most of the nerve. The 
general cutaneous component is small, but has its own ganglion and enters the rami 
cutanei dorsales. The large root of the lateral line nerve of the trunk is conventionally 
assigned to the vagus, though it is really distinct. 
IX nerve . — The glossopharyngeus contains only visceromotor and communisfibers. 
A small bundle of the latter passes by intra-cranial anastomosis into the root of the 
n. lateralis vagi. These fibers pass out with the first three or four branches of the n. lat- 
eralis (the first of these being the n. supra-temporalis vagi), accompanying the proper 
lateralis fibers, and ultimately they anastomose with the r. lateralis accessorius. The 
IX nerve in Alenidia lacks the r. pre-trematicus and the r. suiira-temporaHs. 
VIII nerve . — This nerve supplies the usual organs of the internal ear and belongs 
exclusively to the acustico-lateral system. 
]'II nerve . — The facial nerve contains viscero motor, communis, and lateralis 
fibers. The communis fibers form the whole of the pre-auditory fasciculus communis, 
are provided with a special ganglion, the geniculate g., and are distributed to nearly 
all of the rami of the V + VII complex, as follows: (1) To the r. palatinus (compris- 
ing the whole of that nerve), for the mucosa and taste buds of the roof of the mouth; 
(3) to the truucus hyomandibularis VII, for the mucosa and taste buds of the inside 
of the lower jaw and lip; (3) to the r. niaxillaris V, to taste buds within the upper lip; 
(4) fibers passing dorsally into the cranial cavity, forming in the meninges an elaborate 
plexus, and finally combining to form the facial root of the r. lateralis accessorius 
(r. recurrens VII), which runs the length of the body superficially near the median 
line. (5) Other communis fibers supply some terminal buds on the top of the head 
and run forward with the ophthalmicus superficialis. ((!) In addition to the i)re- 
ceding, there is a small twig which leaves the geniculate ganglion between the truncus 
hyomandibularis and the r. palatinus, running directly ventrally to the roof of the 
mouth, supplying its mucosa in the region between the areas supplied by the IX and 
palatine nerves. It passes along the cephalic face of the very large pseudobranch 
and also innervates this organ. This nerve represents, apparently, the pre-trematic 
branch of the facial, the truncus hyomandibularis being the post-trematic. The 
pseudobranch of this fish, then, represents a vestigeal spiracular gill on the mandible, 
such as Ave find a rudiment of in the adult Torpedo. 
The acustico-lateralis component of the VII nerve is represented by two lateral 
line roots. («) The ventral lateralis root has a separate ganglion and supplies organs 
of the opercular and mandibular canals, via the truncus hyomandibularis. {h) The 
dorsal lateralis root also has a separate ganglion and supplies organs of the infra- 
