OLFACTORY CENTERS IN TELEOSTS 183 
in the nervous anatomy of higher forms. In the case of fiber 
tracts the customary methods of neurological nomenclature have 
been followed, viz., the application of a term which will include in 
itself full information as to the origin and termination of the 
fibers as well as their direction; as for example, the tractus inter- 
medio-habenularis, originating in the nucleus intermedius and 
terminating in the habenula. 
1. PERIPHERAL OLFACTORY APPARATUS 
a. The olfactory capsules 
The olfactory apparatus in the carp consists of the olfactory 
capsules with their lamellae, open to the exterior through two 
apertures; the olfactory nerves, bulbs, crura, centers in the cere- 
bral hemispheres, epithalamus, medithalamus and hypothalamus, 
to which may be added the motor connections common to the 
olfactory and gustatory senses, etc. These latter will not be 
considered in this article. 
Gross morphology. The two external apertures of the capsules 
are in close. proximity, one rostro-medial of the other. They are 
separated by a grooved flap of skin so shaped that in forward 
movement water will be driven into the more rostral aperture. 
The lateral aperture opens caudally for the exit of water from the 
cup. Inside the capsule, and running caudo-laterally from the 
rostro-medial aperture, is a median ridge from which the lamellae 
radiate on either side and at its caudo-lateral end. 
Microscopic anatomy. The lamellae are covered by the epi- 
thelium of the olfactory mucous membrane, consisting of the 
typical nervous olfactory cells, and the supporting cells. Goblet 
cells are particularly numerous in the epithelium of the central 
ridge, which is also slightly thicker than that of the lamellae 
(fig. 5). It resembles closely the respiratory epithelium of the 
Schneiderian membrane of mammals, as distinguished from the 
olfactory portion. It is probable, therefore, that there are found 
here two varieties of epithelium, similar to the condition in higher 
forms; an olfactory, concerned with smell and a respiratory, 
concerned, in this case, with the water current. 
