During the past twenty years sternal marrow examination has become increasinp'ly important in the study of diseases of the blood forming organs. i .ïany reviews of the importance of this method of investigation have appeared in the literature from time to time but some of them have concentrated on only one aspect of the subject, whilst the more comprehensive ones have failed in some respects to deal adequately with the subject.

In the second part of the thesis is a detailed account of the value of marrow examination in diagnosis, prognosis and treatment of the diseases of the blood forming organs, based upon my own personal ex:cerience of approximately eighty cases, which necessitated the .performance of over a hundred sternal punctures.

The first part of this thesis is devoted to a comprehensive review of this subject and includes a description of a method of, procuring marrow by sternal puncture and the technique of staining smears.