OLFACTORY CENTERS IN TELEOSTS 205 
cells, appearing as a core in the center of the nucleus (figs. 84, 
89). Rostrally, the nucleus anterior tuberis is continuous past the 
fibrae ansulatae, Herrick’s commissure, ete., into the nucleus 
preopticus, pars parvocellularis posterior. Caudally, the nucleus 
ends at the level of the lateral ventricular diverticula, leading to 
the lobi laterales (figs. 100,101). See also Edinger (’08), fig. 171; 
Goldstein (05), text-fig. 16. 
Nucleus posterior tuberis. Dorsad of the diverticula the nu- 
cleus anterior tuberis passes caudally into the nucleus posterior 
tuberis, immediately ventral to the tuberculum posterius (Hau- 
benwulst) (fig. 103). This is a nucleus of small cells, similar in 
appearance to those of the nucleus anterior tuberis, although its * 
celis are more evenly distributed. 
Nucleus ventralis tuberis. Appearing rostrally, immediately 
ventral to the commissura horizontalis, is a nucleus of enormous 
cells, not hitherto described in the literature, which is here termed 
the nucleus ventralis tuberis (fig. 78). It continues for a short 
distance caudally, lying close underneath the median ventricle 
and gradually diminishing in size (figs. 81, 84). . 
Nucleus lateralis tuberis lLaterally, appearing immediately 
caudal to the commissura horizontalis, at the ventro-lateral mar- 
gin of the nucleus anterior tuberis, occurs a closely packed group 
of large cells, the nucleus lateralis tuberis (fig. 84). This is found 
only for a short distance at the level of attachment of the hypo- 
physis. . 
Nucleus ventricularis. Close to the median ventricle, parti- 
cularly as far caudal as its diverticula, may be seen a layer of 
densely packed cells close against the ependyma. Similar cells 
may be noted adjacent to the median ventricle rostrally, even 
before the anterior commissure. The same condition holds 
also for the walls of the lateral diverticula into the lobi laterales. 
It is noticeable that wherever these cells are found the ependyma 
consists of higher columnar cells than in other regions. These 
probably belong to the apparatus, described by Johnston, for 
the regulation of blood pressure in the brain. 
Nucleus diffusus lobi lateralis. Throughout the peripheral 
portion of the lobi laterales, particularly laterally and ventrally, 
