No. 3.] LATERAL LINE OF AMIA. PRRs 
the organs of the dorsal pit line, is still given off in Amia from 
the end of the nerve supplying the organs of the supratem- 
poral commissure. As this anterior branch became larger and 
more important, concomitantly with the change of the pit line 
to a canal, it would become the anterior part of the main 
nerve, and the branches to organs 5 and 6 would arise close 
together from it, as they do in Amia. 
Organs 11, 12, and 13 form the third group of the line. They 
are innervated in different specimens by one or by two branches 
of the R. buccalis, the branches, where there are two of them, 
arising close together and close to the origin of the main nerve 
from its ganglion, and one of them supplies organs 11 and 12; 
where there is but one, the branch to organ 13 arises close to 
the origin of the nerve from the main R. buccalis ; thus repre- 
senting a stage in which the division of the nerve has not 
proceeded far enough to give rise toa separate branch. The 
branches to the different organs enter the bony canal of the 
suborbital line by separate passages, immediately below the 
proper organ. 
The next three organs, Nos. 14, 15, and 16, form the fourth 
group of the line, and vary somewhat in their method of inner- 
vation. Organs 15 and 16 are always supplied by branches of 
the R. oticus facialis. This nerve arises directly from the 
facial ganglion. It runs upward and outward without entering 
the orbit, and, piercing the cranial cartilage, issues on the top 
of the chondrocranium at the extreme anterior end of the 
diverticulum of the temporal groove. It here separates into 
three branches, two of which supply organs 15 and 16, and one 
the organ at the upper end of the spiracular canal. 
Organ 14 is sometimes supplied by a branch given off by the 
ramus oticus after it makes its exit on top of the cranium; 
but oftener, in the specimens examined, it was innervated by a 
branch which left the nerve close to its origin, or even from the 
facial ganglion itself, near the root of the oticus, but a little in 
front of it. This branch, after making its exit into the orbit 
through the regular foramen for the ophthalmic nerves, turns 
upward and reaches its proper organ without piercing the 
cranium at all, or passes through a special perforation in the 
overhanging cartilaginous roof of the orbit. 
In young specimens the buccal and ophthalmic branches of 
