NERVUS TERMINALIS IN AMIA 107 



sequently, only a few points will be mentioned here. In a speci- 

 men about 12 mm. long cut sagitally, there was found a slender 

 fibrous connection from the ganglion of about a dozen cells, 

 running posteriorly beneath the olfactory nerve to the brain wall. 

 As there was a small blood vessel on the brain wall just at this 

 point, it cannot be said whether the fibrous connection is a root 

 of the nervus terminalis or a fiber to the blood vessel. The cells 

 are embryonic in appearance and many of them certainly do not 

 possess nerve fibers until a much later date. As in Amia, the 

 ganglion develops during very late embryonic stages. In a 

 Lepidosteus over 85 mm. long, the ganglion of fifty cells or more, 

 is located about half way from the olfactory bulbs to the nasal 

 capsule; but in adults the main mass of cells lies peripherally in 

 the nasal capsules. Nissl preparations of adult nasal capsules 

 show ganglionic masses of these cells lying among the olfactory 

 fibers at the base of the main folds of the Schneiderian membrane, 

 of which there are about twelve. Also, the ganglion has been found 

 in the young of what was thought to be the short-nosed gar 

 (Lepidosteus platostomus). 



While this manuscript was being written, preparations have 

 been made which show conclusively that we have in teleosts 

 a nerve very similar to the nervus terminalis of Amia and Lepi- 

 dosteus. In the carp (Cyprinus carpio) there were found about 

 three hundred ganglion cells scattered along a more or less dis- 

 tinct and separate strand of the olfactory nerve of a specimen 

 about one-fourth meter long. In the historical sketch we have 

 already cited Sheldon ('09) as having found in the carp the central 

 connection of the nervus terminalis with the brain. The cells 

 are somewhat larger than the sheath cells of the olfactory nerve, 

 as in Amia, and are situated on the ventro-median side of the 

 olfactory nerve in the nasal capsules. Their number diminishes 

 as the olfactory bulbs are approached. The single Cajal prepara- 

 tion so far made to show the fibers, makes it evident that they are 

 slightly coarser than the olfactory fibers, as in Amia, and that they 

 are distributed everywhere in the nasal capsules, and that the 

 main bundle turns dorsad from the ganglion cells to the region 

 of the mid-rib. A full description of the condition in teleosts 



