214 JouRNAL OF CoMPARATIVE NEUROLOGY. 
outer wall of the cranium cephalad of the IX ganglion, main- 
taining the same relation to the IX nerve until that nerve enters 
the first gill, At that level along narrow ganglion appears 
in the chain. This ganglion appears close behind the point of 
exit of the hyomandibular trunk from its foramen and it com- 
municates with this nerve and with the r. palatinus posterior. 
Unlike most other vertebrates, the sympathetic ganglionated 
chain does not touch directly either the vagus or the glosso- 
pharyngeus nerves at any point. 
The sympathetic chain enters the trigemino-facial ganglionic 
complex with the hyomandibular trunk, and I was not able to 
trace its entire course through the complex. Apparently it 
divides, some fibers running forward along the outer suface of 
the complex and some farther mesially, the former strand prob- 
ably entering the infra-orbital trunk. The latter strand reap- 
pears at the level of the exit of the oculomotor nerve from its 
foramen as a detached non-ganglionated strand of non-medul- 
lated fibers which runs out closely joined to the III nerve. Just 
cephalad of the point where the nerve for the m. rectus supe- 
rior separates from the III nerve there is a small sympathetic 
ganglion of only six to ten cells. After the branch for the 
m. rectus inferior has separated from the III nerve the sympa- 
thetic also separates from it and immediately presents another 
small ganglion lying just dorsally of the m. rectus inferior be- 
tween it and the orbital vein. From this ganglion a clearly 
defined compact bundle of fibers runs out laterally under the 
vessel just mentioned and reaches the eye-ball slightly caudad 
of the point where the optic nerve enters it. This nerve is 
clearly the r. ciliaris brevis. 
Part II. THe Curaneous SENSE ORGANS. 
Under this head it is proposed to present a few observa- 
tions upon the two systems of cutaneous sense organs so abun- 
dantly scattered over almost the entire body surface of Amer- 
ican siluroids; viz. the organs of the lateralis and terminal bud 
systems. We have seen in the previous sections that these two 
systems are very distinct in their innervation, the former being 
