So-called mixed leukemia, that is, a combination of myelogenous and lymphatic leukemia occurring in one person at the same time, is such a rare condition that I have felt it worth while to report this case, as well as enter into the problem which a study of the case presents and to review the literature on previously reported cases.
Türk1 was the first to report a case of so-called mixed leukemia. This was in 1906, before the congress of Internal Medicine. He reported four cases at this time which he considered to be mixed leukemia. He apparently was the first to appreciate, at least, to publish the fact that an activity of the lymphatic and myeloid systems could go on in an individual at the same time. In the same year, Hirschfeld2 reported a case which he called true mixed leukemia, and in 1909, Herz3 reported a case which he