A study of the neutral lipids and phospholipids of the acanthocephala Macracanthorhynchus hirudinaceus and Moniliformis dubius

1. 1. The neutral lipids and phospholipids of male and female Macracanthorhynchus hirudinaceus and Moniliformis dubius have been studied. 2. 2. M. dubius contained some four times more lipid than M. hirudinaceus and the bulk of the higher fat content was glycerides. A sex dimorphism was observed in both species. The male worms contained almost twice the total lipid that was present in the females. 3. 3. The esterified fatty acids from the neutral lipid fractions were analyzed gas-chromatography of their methyl esters. Acids from C 10 through C 20 were present in both species and the C 18 acids accounted for over 70 per cent of the total acids. 4. 4. The phospholipids of both species contained ethanolamine, serine, choline and inositol phospholipids. Plasmalogens were also found in the phosphate containing lipids.