Spi
no
ce
ph
a
li
c
tr
a
c
ts
?
Spi
no
ce
ph
a
li
c
tr
a
c
ts
?
VVentral funiculusentral funiculus
VVentral grayentral gray
Intermediate grayIntermediate gray
Superficial fasciculus gracilis
Deep fasciculus gracilis
Dorsal root
collateralization zone
Lateral
funiculus
Lateral
funiculus
Lateral
corticospinal
tract
Lateral
corticospinal
tract
Clarke's
column
Clarke's
column
Vestibulospinal tract
Dorsal grayDorsal gray
Dorsal funiculus
Myelinating terminals
of dorsal root collaterals
Central canal with
surrounding ependyma
Dorsal root
bifurcation zone
Lissauer's
tract
Lissauer's
tract
Incipient
subgelatinosal
plexus
Incipient
subgelatinosal
plexus
Reticulated
area
Reticulated
area
I
n
tr
aspina
l
tr
a
c
ts
?
I
n
tr
aspina
l
tr
a
c
ts
?
S
p
in
o
c
e
re
b
e
ll
a
r
tr
a
c
t
s
?
S
p
in
o
c
e
re
b
e
ll
a
r
tr
a
c
t
s
?
Dorsal median septum
Ventral
median
fissure
VVentral gray commissureentral gray commissure
VVentral white commissureentral white commissure
The increased density of the myelin stain that was interpreted to be the rubrospi-
nal and lateral reticulospinal tracts in Plate 54 cannot be detected in this section,
so these fi ber tracts are not labeled. However, the medial and central fi bers in the
intraspinal tracts have a greater staining density than the dorsolateral parts. That
same gradient is seen in the thoracic cord of the GW26 specimen (Plate 51).
PLATE 56B