Unsaponifiable Material.

We paid special attention to the nature of the unsaponifiable matter in these marine oils, for the following reason: One of us (C. L. C.) has already demonstrated that “mutton-bird oil” consists mostly of cetyl-oleate and other esters of cetyl alcohol. For some time we have been investigating the fate of cetyl alcohol in the body, and, incidentally, its origin in the mutton-bird. One possibility that presented itself to our minds is that the oil may be an indigestible (i.e., unsaponifiable) residue of the fat present in the food of the bird. The finding of cetyl alcohol in whale-feed or other shell-fish, or in the fats of any form of marine life, would lend support to such a view, but, in spite of much time and labour spent in crystallizing out the unsaponifiable constituents, no trace of cetyl alcohol was found; on the other hand, there was clear evidence that the great mass of it consisted of cholesterol in more or less pure form.

In conclusion, we beg to thank the University of Otago for facilities given us for carrying on this work, and to acknowledge financial assistance received from the New Zealand Institute Research Fund.