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The American Naturalist. [March, 
ZOOLOGY. 
The Central Nervous System of Teleosts.—In the last 
number of La Cellule, a preliminary paper by Van Gehuchten on the 
central nervous system of the trout' adds several points of considerable 
interest to our already large stock of knowledge of the structure of the 
nervous system of vertebrates as determined by the epoch-making 
Golgi methods. Its value, and that of other papers by competent 
students, lies not only in adding so much to the known facts con- 
cerning the lower vertebrates, but more especially in the light that 
it throws upon obscure points in the cerebral structure of the higher 
animals and of man, where the central organs are so large and complex 
as to render investigation very difficult and even impossible. The 
older writers, Stieda, Fritsch, Rabl-Riickhardt, Edinger and others, 
concerned themselves almost wholly with the homologies of the brain 
of Teleosts. It was not until 1887 that the Golgi method was first em- 
ployed with them by Fusari. Since then, Schaper, P. Ramon and 
Retzius have used it. And, if to their work we add that of Nansen and 
Retzius on the nervous system of Petromyzon and that of v. Lenhossek 
on that of Pristivrus, the list will be almost complete for fishes in gen- 
eral. 
Van Gehuchten takes up (1) the structure of the anterior lobes, 
which, by the way, are homologous, as shown by Rabl-Riickhardt, with 
the caudate and lenticular nuclei only of the human brain; (2) the 
origin of the fibres of the cerebral peduncle; (3) the origin and termi- 
nation of the fascicle of Meynert ; (4) some of the constituent elements of 
the optic lobes ; (5) the origin and termination of the olfactory fibres ; 
(6) the origin of the oculomotor communis ; (7) origin of the facial nerve ; 
(8) the origin and the peripheral and central terminations of the audi- 
tory nerve; (9 and 10) the elements of the Gasserian ganglion, of the 
trigeminal nerve and of the large ganglion in the course of the pneu- 
mogastric, as also of the arrangement of the fibres of these in the cere- 
bral trunk. 
Regarding the anterior lobes and the cerebral peduncle, the most 
important fact brought out is that the latter is composed of both as- 
cending and descending fibres, or, to use the terminology recently pro- 
posed by Fish, neurites. The former cannot therefore be regarded with 
1 Le System nerveux des Téléeostéens, La Cellule, Vol. X, pp. 255-95, with 3 
pls. 
