Abstract
Seven specimens of the yellow-fin, Thunnus macropterust (T. & S.), caught in the South-Sea in November to December, 1937 (Table 1) were promptly eviscerated and preserved in a frozen state at about -7°C for 3-4 months. They were then melted, and 500-800g. of each of such five bodily parts as shown in Fig. 1 and also of gonad were canned at 6 lbs. for 1•5 hours. The material from each can underwent ether extraction which yielded respective fats ranging on the average from 145•7 to 191•8 in iodine value and from 1•4727 to 1•4758 in refractive index (Tables 2 & 3). remarkably enough, the fat from the dark muscle was found to have the highest iodine value in spite of low refractive index.
