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IOWA ACADEMY OF SCIENCE 
it supplied the dorsotrachealis muscle. In 1904 I read a paper 9 be- 
fore the Iowa Academy of Sciences describing this nerve, showing 
that it did not end in the dorsotrachealis muscle, even if it supplied 
that muscle, but passed posteriorly into the trunk region as far 
posteriorly as the pelvis. I suggested a possible relation to the 
neuromasts of the trunk, and provisionally designated the nerve 
as the R. lateralis VII. In the same year appeared the paper of 
Druner in which he gave a brief description of the nerve, designat- 
ing it as N. lateralis VII, asserting that it supplied in part the 
median series of neuromasts of the trunk, that is, he considered 
it as a lateral line nerve. The following year I published a second 
paper 10 in which I withheld the name, N. lateralis VII, believing 
that the evidence of the presence in it of lateralis fibers was not 
convincing. I can now assert with considerable confidence that the 
nerve contains lateralis fibers. 
After the fibers destined to form the mentalis VII leave the 
trunk of the dorsal VII the latter passes anteriorly into its ganglion 
lying just dorsal to and confluent with the gasserian ganglion. 
Anteriorly to the ganglion the lateralis fibers are joined by general 
cutaneous fibers from the gasserian ganglion. The latter fibers 
are in two distinct bands, of which one is applied to the ventral and 
the other to the median surface of the lateralis trunk. As the 
combined nerves pass anteriorly the general cutaneous components 
shift their positions, the median band becoming dorsal and the 
ventral ones shifting to a lateral position. The main trunk soon 
divides into a dorsal and a ventral division, each consisting of 
lateralis and general cutaneous fibers. The ventral, or infra-orbital 
division, evidently represents the maxillaris V and the buccalis VII, 
while the dorsal supra-orbital portion is made up of an ophthalmi- 
cus superficialis VII and of what we may term the ophthalmicus 
superficialis V. Each division now divides into two rami. The 
infra-orbital trunk forms the maxillaris V, of general cutaneous 
fibers, and the buccalis VII, of lateral line fibers. The latter after 
giving off twigs to the posterior portion of the infra-orbital series 
of neuromasts divides into two branches. One of these, the dorsal 
and larger, unites with a branch of the ophthalmicus profundus 
nerve, and the combined trunk of general cutaneous and lateralis 
fibers, supplies the skin and the neuromasts of the infra-orbital 
series along the side of the snout. The smaller ventral branch of the 
9. Norris, H. W. The So-called Dorsotrachealis Branch of the Seventh Cranial Nerve 
in Amphiuma. Proc. Iowa Acad. Sci., Vol. X, 1904. 
10. Norris, H. W. The so-called Dorsotrachealis Branch of the Seventh Cranial Nerve 
in Amphiuma. Anat. Anz., Bd. 27, 1905. 
