Comparative studies of bile salts, myxinol disulphate, the principal bile salt of hagfish (Myxinidae).

1. The principal bile salt, myxinol disulphate, of two hagfish species, Eptatretus stoutii and Myxine glutinosa, has been shown by chemical methods and by optical-rotatory and mass-spectral considerations to be probably the C-3,27-disulphate ester of 3beta,7alpha,16alpha,27-tetrahydroxy-5beta-cholestane. 2. Myxine liver sterols were about half ;free' and half esterified: cholesterol only was identified. 3. The chemical nature of myxinol is what might be expected for the bile alcohol of a very primitive vertebrate.