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foramen into the eye muscle canal. The two bundles 
separate in front, but for a time the union is so close that 
they could not be satisfactorily analysed. However, most 
of the profundus fibres proximal to the ciliary ganglion 
separate out as the Ramus ciliaris longus (cd. l.), but a 
few of them accompany the sympathetic to the ciliary 
ganglion (ec. g.) as its Radix longa (re. /.). The R. 
ciliaris longus leaves the eye muscle canal in front and 
accompanies the right rectus superior muscle to the eye, 
which it enters from above. <A true Ramus ophthalmicus 
profundus is therefore absent in the Plaice. 
On the left side the profundus nerve only separates 
from the root of the trigeminus just before the latter 
reaches the Gasserian ganglion. The only other differ- 
ences between the two sides are in matters of detail 
(cp. the description of the sympathetic). 
The only other Teleost which is said to possess a 
separate profundus nerve and ganglion is T'rigla, in 
which, according to Stannius, it is in exactly the same 
condition as in the Plaice, except that it leaves the skull 
cavity by a special foramen. A vestigial profundus nerve 
is also described by Herrick in Menidia. Its occurrence 
in the Plaice in the form described above is therefore of 
exceptional interest. Stannius missed it altogether in the 
Plaice, and hence his statement that the v.-vii. complexes 
of Z'reg/a and Pleuronectes only differ in this respect is 
inaccurate. 
2. Ramus ophthalmicus superficialis (7. oph. sup. v.). 
—Arises from the narrowed anterior extremity of the 
Gasserian ganglion, and constitutes the trigeminal portion 
of the Truncus supraorbitalis. It accompanies the nerve 
of the same name from the facial for a considerable dis- 
tance, being at different places more or less intermingled 
with it. In front, however, it separates from the facial 
