42 
Nachdruck verboten. 
Additional Notes on the Teleost Brain. 
By C. L. Hekeiıck. 
With 10 figures. 
In numbers 23 and 24 (Vol. VI, 1891) of this periodical several 
results of a study of the cerebrum of bony fishes were noticed. It 
appears that some misapprehension has arisen from the fact that, in 
describing the distinct areas detected in the axial lobe, terms were 
used in a descriptive sense which have also been applied to areas of 
the cortex. Notwithstanding the fact that it was distinctly stated 
that these areas belong to the axial lobe, I have been credited with 
an attempt to homologize parts of the axial lobe of fishes with 
cortical areas of mammals, a position which was distinctly disclaimed. 
Nevertheless a farther study shows that it is possible to carry the 
comparison farther than was then supposed. A great deal of fresh 
material, embracing embryological as well as European marine and 
freshwater specimens, shows that the areas or lobes described are very 
constant (though variable in relative extent) and the differences in 
cellular structure are also constant. Moreover it has proven possible 
by the aid of thin sections and high powers (oil-immersion lenses) to 
trace the fibres of the peduncular and other tracts to the processes 
of these cells in several cases. I crave permission to offer a brief 
synopsis of the results which will be elaborated and illustrated by 
ten plates in the forthcoming Journal of Comparative Neurology. 
1. It has proven possible to trace the fibres of the radix 
mesalis olfactorii to the cells of the pes or axial portion of 
the „tuber olfactorii“, thus substantiating a suggestion made sometime 
since. 
2. In very young specimens of Amiurus, cut in the plane of cur- 
vature of the radix lateralis, the fibres can be followed along 
the ventral surface of the cerebrum from the pero or mantle-portion 
[not „mouth-portion“ as misprinted in the previous paper] to the 
region called hippocampal nidulus by us. There is absolutely 
no possibility of any other connection as the entire course is visible 
in one section and the distinction is complete. I am unable to sug- 
gest any better term for this terminus of the specific olfactory tract 
and regard it as the homologue of those cells which occupy the hippo- 
