brainstem consists of the entire caudal region of the
brain beneath the cerebellum, behind the thalamus, and
in front of the spinal cord. It is the huge stalk of the
brain which contains all the sensory, motor and interconnecting
cellular groups, together with all the fiber tracts which
pass through this region. The fiber tracts that interconnect
the forebrain (thalamus, basal forebrain, and cerebral
cortex), spinal cord, and cerebellum.
region of the brain is depicted above in the coronal sections
of one manatee, #85-32, which extends from the caudal
part of the thalamus down to the rostral portion of the
spinal cord (that is, the first cervical spinal segment
within the vertebrae of the upper neck.