THE FREQUENT association of hypercholesteremia with hypothyroidism and particularly myxedema allows one to postulate that a secondary eruptive form of xanthomatosis should occasionally occur in either of these conditions. Actually, only three such reports have been published in which the occurrence of this type of xanthomatosis with either of these diseases has been noted.1 This paucity of reports makes one wonder whether the hypercholesteremia alone is the deciding factor in the formation of the secondary eruptive xanthomatosis in myxedema or whether some other related but as yet undisclosed abnormality, such as essential familial hypercholesteremia, acting as an additive factor, precipitates this eruption. In none of the three previously reported patients had a pedigree for essential familial hypercholesteremia been reported. One of the problems then to be answered is to ascertain whether xanthomatosis associated with myxedema is due to the summation effect of the hypercholesteremia due to the myxedema