Lieutenant-Colonel Theodore Roosevelt '09, son of the former President, will speak in the Living Room of the Union tomorrow evening at 8, as the ninth lecturer in the main series of lectures being held at the Union. "Participation in Public Life" will be the subject of his address.

Previous to his lecture he will attend a dinner given in his honor by the Governing Board of the Union. The guests at this dinner will include, beside the Governing Board, Professors A. C. Coolidge, G. H. Edgell, Theodore Lyman and R. B. Merriman, who will introduce the speaker. Saturday night the Colonial Club will give a dinner for Colonel Roosevelt, but his only public appearance in Boston will be at the lecture in the Union.