BLOOD - AIR
PHLEGM - WATER
YELLOW BILE - FIRE
BLACK BILE - EARTH
All four of these humors, or vital fluids, are present in the bloodstream in varying quantities:
Blood, or the Sanguine humor, is the red, hemoglobin-rich portion.
Phlegm, or the Phlegmatic humor, is present as the clear plasma portion.
Yellow Bile, or the Choleric humor, is present as a slight residue or bilirubin, imparting a slight yellowish tint.
Black Bile, or the Melancholic humor, is present as a brownish grey sediment with platelets and clotting factors.