No. 3.] MUSCLES AND NERVES [IN AMIA CALVA. 543 
undoubtedly represent the portio ophthalmici profundi of Amia, 
or that nerve and the superficialis trigemini also. Under 
these branches, but, so far as can be judged from Pinkus’ 
Fig. 1, above the remaining main portion of the nerve, the 
nervus oculomotorius and nervus abducens run, from within 
outward, to the muscles of the eye. In the text Pinkus says 
that the oculomotorius leaves the profundus on its ventro-lateral 
side. The position of the main profundus relative to the supe- 
rior and inferior branches of the oculomotorius is, therefore, left 
somewhat in doubt, as is also its relation to the abducens. 
In Petromyzon the ramus ophthalmicus trigemini lies under 
the nervus trochlearis, but, if Firbringer’s figure is correct, 
over the superior branch of the oculomotorius. There is no 
other ophthalmic nerve, and that the terminal buds in Petro- 
myzon are homologous with those in Amia seems from Merkel’s 
description an open question. The “Nervenhiigel’’ that he 
describes in Petromyzon seems to resemble the “ Nervensicke”’ 
rather than the “ Nervenhiigel”’ of ganoids, and the nerve in 
that case in Petromyzon would probably be the profundus, as 
its position below the trochlearis indicates, rather than the 
superficialis, which, in all other fishes, lies always above that 
nerve. 
In Salamandra and Rana (Schwalbe) the ramus nasalis trige- 
mini lies under the trochlearis, under the rectus superior, and 
under the nerve supplying that muscle. In Salamandra it lies 
also under the branch to the rectus internus. It, therefore, cor- 
responds exactly in position to the ophthalmicus profundus of 
selachians, as Schwalbe has himself pointed out (No. 113, p. 
200). In both Salamandra and Rana a ciliary ganglion is 
described by Schwalbe as a ganglion of the oculomotorius, 
connected in Rana with the ramus nasalis by a very delicate 
radix longa, and probably so connected in Salamandra also, 
although Schwalbe did not find the nerve. In Salamandra, 
and also in Menobranchus and Siredon, ciliary branches arising 
from the ramus nasalis are described in addition to those aris- 
ing from the ciliary ganglion. In Rana and Salamandra rami 
frontales are described, arising from the base of the ramus 
nasalis and considered by Schwalbe as the equivalents of the 
