No. 3.] MUSCLES AND NERVES IN AMIA CALVA. 601 
their relations to each other vary greatly in different specimens. 
On the left side of the head, in the specimen here described, 
the facialis branch to organ 7 was accompanied by the anterior 
of the two trigeminal branches that form the second pair, the 
other trigeminal branch of the pair issuing by a separate and 
slightly lateral canal. On the right side the facial branch to 
organ 7 joined the inner one of the first pair of trigeminal 
branches, those forming the second pair issuing separately by 
two somewhat anterior openings. On both sides of the head 
there were, associated with these first two pairs of frontal 
nerves, one or two branches of a nerve which arose from the 
trigemino-facial ganglion under and lateral to the root of the 
ophthalmicus trigemini and which will be later described as 
nerve ‘a.’ On the left side of the head these branches of nerve 
‘a’ pierced the cranial cartilage near its lateral edge and issued 
on the top of the cranium lateral to and slightly in front of 
the two pair of trigeminal branches; on the right side, where 
two pair of frontal nerves issued at some distance apart, the 
branches of nerve ‘a’ issued lateral to, but between them. 
The next branch of the ophthalmicus facialis is the one to 
organ 6 supraorbital. It runs upward and backward external 
to the cranial cartilage, lying in or just in front of a strong 
notch in the cartilaginous roof of the orbit. Ona level with 
this nerve, in the specimen used, four branches arose from the 
ophthalmicus trigemini on the left side of the head, and three 
on the other. One of the branches on the left side, and two of 
those on the right, lay internal to, or above, and the others 
external to, or below, the ophthalmicus facialis. Those lying 
internal to the facialis ran upward immediately behind the 
branch to organ 6, either lying in the notch already described, 
or passing through special canals in the cartilage. Having 
reached the upper surface of the cranium, they turned median- 
ward and were distributed to tissues toward the middle line of 
the head. The other branches, issuing below the ophthalmicus 
facialis, ran outward and forward into the fatty tissues above 
the eye. On the right side of the head there were no branches 
from the ophthalmicus trigemini between this group of nerves 
associated with the facialis branch to organ 6 and those asso- 
