What is "hemal arch"

Hemal \He"mal\, a. [Gr. a"i^ma blood.] Relating to the blood or blood vessels; pertaining to, situated in the region of, or on the side with, the heart and great blood vessels; -- opposed to neural.

Note: As applied to vertebrates, hemal is the same as ventral, the heart and great blood vessels being on the ventral, and the central nervous system on the dorsal, side of the vertebral column.

Hemal arch (Anat.), the ventral arch in a segment of the spinal skeleton, formed by vertebral processes or ribs.

n. a structure arising ventrally from a vertebral centrum and enclosing the caudal blood vessels [syn: haemal arch]