Trichophyton rubrum grown in Sabouraud's liquid medium contains phosphatidyl inositol, polyphosphatidyl inositol, phosphatidyl choline, phosphatidyl serine, phosphatidyl ethanolamine phosphatidyl glycerol and phosphatidic acid in the polar lipid fraction of its mycelia. The relative proportion of these components in total phospholipid fraction remains almost constant throughout the culture life of this fungus. © 1974 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.