THE LITERATURE contains few quantitative studies of the lipid composition of brain tumour cells. CUMINGS (1943) found traces of phospholipid phosphorus in astrocytomas, glioblastomas, medulloblastomas and meningiomas. In a more comprehensive study, BRANTE (1949) found the lipid composition of neurectodermal tumours to be similar to that of normal brain except for a larger amount of cholesterol ester in tumour tissue. Later workers ( SELVERSTONE and MOULTON, 1957;COHEN, 1955; and NAYYER, 1963), concluded that the phospholipid component of gliomas was approximately one-half that found in normal brain. These later studies were restricted to the cephalin, lecithin, and sphingomyelin fractions and differences involved only cephalin and sphingomyelin.More extensive lipid analysis of brain tumours followed the introduction of thinlayer chromatography. CURRI, COSTANTINI and CARTERI (1 963) ; CURRI, COSTANTINI, CARTERI and CIOFFI (1964); GOPAL, GROSSI, PAOLETTI and USARDI (1963) and CHRISTENSEN-LOU, CLAUSEN and BIERRING (1965) reported small amounts of phospholipids and no cerebrosides in meningiomas, neurilemmomas, and metastatic tumours from the breast and cervix. Astrocytomas and glioblastomas contained phospholipid in amounts comparable to adjacent brain tissue. Cerebrosides were present in all samples of normal brain and in most glioblastomas, but were absent in one of two astrocytomas. GOPAL et al. (1963) found that brain tumour tissue contained two to three times more fatty acids, sterol esters, and glycerol esters than normal brain. A high percentage of lecithin and small percentages of cephalin , sphingomyelin and lysolecithins characterized tumour tissue. CHRISTENSEN-LOU et al. (1 969, using a photometric scanning procedure for the quantitative estimation of the phospholipids separated on thin-layer chromatography, measured phosphatidylserine, sphingomyelin, phosphatidylcholine, phosphatidylethanolamine and cerebrosides in glial tumours and in normal brain. Phospholipids in glioblastomas were characterized by a higher proportion of phosphotidylcholine and sphingomyelin and a lower proportion of phosphatidylethanolamine than those in normal brain. Phosphatidylcholine was highest near the centre of astrocytomas. The lipid pattern in tumours resembled the pattern found in normal brain surrounding the tumour. FUMAGALLI, GROSSI, PAOLETTI and PAOLETTI (1964) analysed sterols in brain tumours by gas chromatography and found desmosterol, lanosterol and zymosterol in eleven of thirteen glioblastomas and