1. 1. Sphingosine base distribution was studied in non-ganglioside polar lipids from whole brain of animals in five classes of phylum chordata: rat, chicken, turtle, frog and fish, and from brain and ventral cord of the crayfish of phylum arthropoda. 2. 2. Sphingosine bases were prepared from polar lipids by acid-catalyzed methanolysis. Sphingosine base mixtures were analyzed by periodate oxidation to aldehydes, followed by gas-liquid chromatography. 3. 3. Results obtained indicate trends, in the direction of lower species, towards lower total lipids and polar lipids and much lower glycosphingolipids. Sphingosine base distributions varied among the species, also demonstrating phylogenetic trends. Increased saturation and decreased chain length were observed in the direction of lower species. 4. 4. Possible relevance of these results to differences in myelin between homeothermic and poikilothermic animals are discussed. © 1969.
