By the injection of lipoid extracts of organs (liver, spleen, and lymph nodes) of 5 patients with leukemia, 1 with Hodgkin's disease, and of 4 "control" cases (3 of heart disease and 1 of cerebral tumor) into 28 guinea-pigs, it was observed that:
a. extracts from human myeloid leukemic organs produced "myeloid reactions" or infiltrations in guinea-pigs;
b. extracts from lymphoid leukemic organs produced "lymphoid reactions";
c. extracts from organs involved with Hodgkin's disease produced "Hodgkin's reactions"; and
d. extracts from "normal" organs produced slight lymphoid or monocytoid infiltrations.