front matter 1

Floor plateFloor plate

Central

canal

Ventral horn

interneurons

Ventral horn

interneurons

Intermediate

interneurons

Intermediate

interneurons

Dorsal root

Dorsal root

bifurcation zone

Fasciculus gracilis?

Dorsal root

collateralization zone

Lissauer's

tract?

Lissauer's

tract?

Dorsal funiculus

Dorsal

horn Substantia

gelatinosa

Substantia

gelatinosa

EpendymaEpendyma

Lamina ILamina I

Laminae

IV-V

Laminae

IV-V

Sojourn zone of premigratory

neurons destined for the dorsal

horn and intermediate gray

Intermediate

neuroepithelium

Intermediate

neuroepithelium

Dorsal neuroepithelium

Central autonomic

area

Central autonomic

area

Segregating

ventral horn

motoneuron

columns

Segregating

ventral horn

motoneuron

columns

axial

motoneurons

axial

motoneurons

hip and knee

motoneurons

hip and knee

motoneurons

ankle

and

foot

moto-

neurons

ankle

and

foot

moto-

neurons

Dorsal

canal

Dorsal

canal

Ventral

white

commissure

Ventral

white

commissure

Ventral

median fissure

Dorsal median septum

Retreating roof plate

V

e

n

t

r

al

fu

nic

ulus

V

e

n

t

r

al

fu

nic

ulus

L a t e r a l f u n i c u l u s

L a t e r a l f u n i c u l u s

PLATE 19B