OLFACTORY CENTERS IN TELEOSTS 195 
diately lateral to the fissura endorhinalis, a portion of the nucleus 
pyriformis is specialized to form the nucleus teniae of Kappers, 
Goldstein, Edinger, the caudal portion of the hypostriatum of 
Catois, nucleus occipito-basalis of C. L. Herrick. This is a com- 
pact nucleus of rather small cells (fig. 57). Caudally it meets the 
pars intermedia of the corpus precommissurale, both being covered 
dorsally by the unspecialized cells of the lobus pyriformis (figs. 
30,.00, 66,67, 70). 
In preparations by the Golgi method, this region is plainly 
marked. Throughout the whole lateral olfactory area, near the 
periphery of the lobes, one finds cells of the same general type, 
with fine processes, lightly spiny, and with small sized perikarya 
(figs. 52, 33, 48, 49, 52, 53). The perikarya vary considerably 
in shape, flask-shaped cells being most numerous, as shown in 
figs. 32, 33, from the rostral portion of the lateral area, figs. 48, 
49 from the dorso-lateral part. Occasionally, small pyramidal 
cells of the type shown in fig. 53 may be found. Flask-shaped 
cells are particularly numerous close to the periphery of each lobe, 
with the rounded margin of the perikaryon directed toward the 
periphery and most of the processes arising from the mouth of the 
flask. A cell of this type is shown in fig. 52. Part of these proc- 
esses extend laterally along the ventricular margin, while the 
neurite enters the basal forebrain bundle. 
The cells of the nucleus teniae vary somewhat from the general 
type of the lateral olfactory area neurone but are recognizably 
similar. Many of the cells, as shown in figs. 59, 60, possess peri- 
karya more nearly ovoid than flask-shaped; the processes are 
fine and bear inconspicuous spines, however, as do the other cells 
of the lateral olfactory area. Fig. 58 shows a cell nearly pyra- 
midal in shape. 
(d) Palaeostriatum. In the central part of each basal lobe is 
a region called by practically all writers on the teleostean brain 
the corpus striatum, here termed the palaeostriatum (figs. 25, 38, 
56). It is bounded mesially by the precommissural body, dor- 
sally by the primordium hippocampi and on the other sides by the 
lateral olfactory nucleus. Practically all parts of it receive 
olfactory fibers of the second order and it is largely, therefore, a 
