The Hexamita(= Octomitus) problem: A preliminary report

THE INTESTINAL FLAGELLATE, Hexamita salmonis (Moore), was described in 1922 from trout in hatcheries throughout New York State. At first associated with the so-called whirling disease of brook trout (Salvelinus fontinalis), now believed to be a virus disease, Hexamita was subsequently held responsible for practically any otherwise unexplainable mortality in underyearling salmonids. Over the years, Hexamita, ostensibly H. salmonis, has been the most readily recognized parasite of juvenile salmonids.