“…It can be seen that he still had a mild macrocytic anaemia and that his serum B,, concentration was subnormal, being similar to that seen in moderately severe B,, deficiency Ross, 1952, 1954a). A sternal bone-marrow aspiration performed 28 days after an injection of liver extract revealed the typical findings of a mild megaloblastic anaemia (Dacie and White, 1949). It was therefore apparent that in spite of treatment with z ml.…”