Three novel glycosphingolipids containing five to seven sugars in their saccharide chains have been isolated from larvae of the green-bottle fly, Lucilia caesar. The structures of these glycolipids were identified by sequential enzymatic degradation with exoglycosidases, methylation analysis, and partial acid hydrolysis to be: Gal-NAc alpha (1-4)GalNAc beta (1-4)GlcNAc beta (1-3)Man beta (1-4)Glc-Cer, Gal alpha (1-4)GalNAc alpha (1-4)GalNAc beta (1-4)GlcNAc beta (1-3)Man beta (1-4)Glc-Cer, and GlcNAc beta (1-4)Gal alpha (1-4)Gal-NAc alpha (1-4)GalNAc beta (1-4)GlcNAc beta (1-3)Man beta (1-4)Glc-Cer. It should be noted that one N-acetylgalactosamine in their saccharide chains is alpha-glycosidically linked to another N-acetylgalactosamine by a 1-4 bond and that this is the first example of the presence of an alpha (1-4) linked galactosamine unit in nature. The major fatty acids were normal saturated fatty acids with carbon numbers of 16 to 22. The long-chain bases were dominated by C14 and C16-4-sphingenine homologues.