front matter 1

VVentral funiculusentral funiculus

Ventral horn

motoneurons

Ventral horn

motoneurons

Ventral horn

interneurons

Ventral horn

interneurons

Intermediate

interneurons

Intermediate

interneurons

Dorsal root

bifurcation zone

Fasciculus cuneatus

Fasciculus gracilis

Dorsal root

collateralization zone

Lissauer's

tract

Lissauer's

tract

Dorsal root

with dense

glia in

boundary cap

Dorsal root

with dense

glia in

boundary cap

Ventral root

Dorsal funiculus

Dorsal

horn

Dorsal

horn

Substantia

gelatinosa

Substantia

gelatinosa

Lateral

funiculus

Lateral

funiculus

Central

autonomic

area

Central

autonomic

area

Lateral

cervical

nucleus

Lateral

cervical

nucleus

Lamina ILamina I

Laminae

IV-V

Laminae

IV-V

Central

cervical

nucleus?

Central

cervical

nucleus?

Central canal

surrounded by ependyma

Central canal

surrounded by ependyma

skull

and

neck?

skull

and

neck?

shoulder?shoulder?

arm and forearm?arm and forearm?

wrist?wrist?

digits?digits?

digits?digits?

hand?hand?

Examples of concentrations

of proliferating glia

Dense

Sparse

Dorsal median septum

Dorsal intermediate septum

VVVentral gray commissureentral gray commissureentral gray commissure

VVVentral white commissureentral white commissureentral white commissure

Ventral median fissure

See the matched myelin stained section in Plates 80A and B

The corticospinal tracts no longer stand out as clear areas with very sparse proliferating glia in the white matter. There is a

large area of slightly more dense proliferating glia in the ventral and lateral funiculi that corresponds partly to the regions

that are still myelinating. Refer to the matching myelin stained section for the approximate locations of both corticospinal

tracts, the lateral reticulospinal, vestibulospinal, intraspinal, and spinocephalic tracts.

PLATE 81B