224 RALPH EDWARD SHELDON 
chiefly fibers from the more rostral part of the striatum. He 
traces strio-thalamicus fibers into the nucleus anterior thalami, 
nucleus dorsalis thalami, nucleus ventralis thalami, nucleus pos- 
terior thalami, nucleus anterior tuberis, nucleus lateralis tuberis, 
nucleus diffusus lobi lateralis. The tractus strio-thalamicus. of 
Goldstein includes the tractus olfacto-hypothalamicus lateralis 
of Kappers. Johnston (’02) in Petromyzon states that the trac- 
tus strio-thalamicus is formed from the neurites of the cells of the © 
striatum which end in the central gray of the thalamus. He 
also identifies fibers from the lateral olfactory centers, forming a 
part of his tractus olfacto-lobaris, which correspond to the tractus 
olfacto-hypothalamicus lateralis of Kappers. 
As described here, the lateral forebrain bundle consists of the 
tractus strio-thalamicus, tractus thalamo-striaticus, tractus olfac- 
to-hypothalamicus lateralis and tractus hypothalmo-olfactorius 
lateralis (fig. 139). Rostrally distributed through the central part 
of each lobe, almost at the tip of the basal lobes, may be seen 
in Weigert preparations many bundles of unmedullated fibers. 
Caudally, near the level of the anterior commissure, these bundles 
pass gradually ventrad, lying dorsal to the fissura endorhinalis 
(fig. 34). Thence these turn slightly mesad (fig. 35), constantly 
increasing in size through the accession of new fibers, until at the 
caudal level of the commissure the lateral forebrain bundle appears 
as a powerful tract containing many large bundles of mixed medul- 
lated and unmedullated fibers (fig. 36). As a usual thing the 
medullated fibers either form a sheath for the unmedullated or 
else form separate bundles, the two kinds of fibers being rarely 
intermingled in the same bundle. A large part of the fibers, as 
Goldstein describes, decussate in the caudo-ventral part of the 
anterior commissure (figs. 36, 37). Caudal to the commissure, 
the different bundles become more compactly arranged and extend 
through the pedunculi thalami close against their lateral margins 
(figs. 55, 61, 68). 
The components of the tract, as it passes through the pedunculi 
thalami, are shown in fig. 139. It will be noted that the fibers 
are both ascending and descending and that the several bundles 
have somewhat different connections. In general it may be stated 
