OLFACTORY CENTERS IN TELEOSTS Da 
ston’s tractus strio-thalamicus lateralis arises from cells of the nu- 
cleus postolfactorius lateralis, while the larger part of the tractus 
strio-thalamicus medialis arises from the striatum proper. In 
1901 Johnston modifies these descriptions somewhat. He says 
that the ventral bundle is composed of ascending fibers, as noted 
above, which end in the epistriatum of the opposite side, together 
with descending fibers from the nucleus preopticus. He further 
~ adds that most of the ascending fibers arise from the dorsal and 
lateral walls of the mammillary bodies, and run in the medial 
bundle. Van Gehuchten (’94) also describes ascending fibers in 
the tractus strio-thalamicus, stating that the bundle is made up 
of two kinds of fibers, those which originate in the basal ganglia 
and end in the inferior lobes, and vice versa. Catois observed 
these same two fiber groups one of which is formed by ‘fibers 
motrices descendantes,’ the other by ‘fibres sensitives ascen- 
dantes.’ Catois states that the descending fibers lie external and 
dorsal to the ascending. The descending fibers he traces largely 
into the nucleus rotundus, and also farther ventrally, while a few 
fibers extend into the basal portion of the mesencephalon. The 
ascending fibers are traced by Catois from the region of the infun- 
dibulum, chiefly from the more rostral part. Catois includes 
here the medial forebrain bundle as a part of the tractus strio- 
thalamicus. Kappers traces the tractus strio-thalamicus from 
all parts of his striatum into the pedunculi thalami, ending un- 
crossed partly in the nucleus rotundus, but chiefly in the nucleus 
subrotundus. Kappers has, however, identified a tract aris- 
ing chiefly from the lateral olfactory area, the tractus olfacto- 
hypothalamicus lateralis, which has been included with the tractus 
strio-thalamicus by other authors. This passes caudad, lying 
immediately dorsal to the tractus strio-thalamicus, and ending 
after decussation inthe ventral portion of theinferior lobes. Gold- 
stein has worked out the connections of the tractus strio-thalami- 
cus in considerable detail and finds that it originates from all 
parts of the striatum and that part of its fibers decussate in the 
anterior commissure, as Edinger suggested in 1888. Goldstein 
states that the crossed fibers lie mesal to the uncrossed, and that 
the more dorsal fibers in the praethalamic part of the tract contain 
