Adjective
Pertaining to the blood or blood vessels; also, ventral. See Hemal.
Source: Webster's dictionaryAside from the water vascular system, echinoderms have a haemal coelom (or haemal system, the "haemal" being a misnomer), a perivisceral coelom, a gonadal coelom and often also a perihaemal coelom (or perihaemal system). Source: Internet
Granite Hill Publishers, 2003. p. 271. The water vascular system, haemal system and perihaemal system form the tubular coelomic system. citation Echinoderms are an exception having both a coelomic circulatory system (i. Source: Internet
Many mammals have tiny spleen-like structures known as haemal nodes throughout the body that are presumed to have the same function as the spleen. Source: Internet