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 gracilis

Dorsal root

collateralization zone

Lissauer's

tract

Dorsal funiculus

Dorsal

horn

Dorsal

horn

Substantia

gelatinosa

Substantia

gelatinosa

Lateral

funiculus

Lateral

funiculus

Central

autonomic

area

Central

autonomic

area

Lateral

horn

motoneurons

Lateral

horn

motoneurons

Lamina ILamina I

Laminae

IV-V

Laminae

IV-V

Clarke's

column

Clarke's

column

Central canal

surrounded by ependyma

Central canal

surrounded by ependyma

middle

trunk?

middle

trunk?

Dorsal median

septum

VVentral gray commissureentral gray commissure

VVentral white commissureentral white commissure

Ventral median fissure

Lateral

corticospinal

tract?

Lateral

corticospinal

tract?

See the matched myelin stained section in Plates 84A and B

This caudal section shows a slight reduction in the concentration of proliferating glia in the lateral corticospinal

tract; that suggests a rostral to caudal gradient in the myelination of the lateral corticospinal tract. There is also a

region of slightly greater density in the ventral and lateral funiculi. Refer to the matching myelin stained section

for the approximate locations of the lateral reticulospinal, vestibulospinal, intraspinal, and spinocephalic tracts.

PLATE 85B