- Matings from crossing biochemical mutants of E. coli experiment1
- Matteawan State Hospital, Beacon, N.Y: Exterior view- Administration Building1
- Matteawan State Hospital, Beacon, N.Y: Exterior view- Administration Building with adjoining ward1
- Matteawan State Hospital, Beacon, N.Y: Exterior view- Employees Home1
- Matteawan State Hospital, Beacon, N.Y: Exterior view- Female housing unit1
- Matteawan State Hospital, Beacon, N.Y: Exterior view- Reception Hospital1
- Max Delbruck and Salvador Luria at Cold Spring Harbor Laboratory1
- Max Lurie1
- Maxine Singer, Bruce Ames, Jesse Rabinowitz, and Victor Ginsburg playing wind instruments1
- Mechanism of Action of Penicillin1
- Medical Society of the District of Columbia: Annual Scientific Assembly2
- Medical Society of the District of Columbia: Dr. Edgar Copeland, Judge Youndahl, Dr. Magruder MacDonald and Dr. Joseph Wall1
- Medical Society of the District of Columbia: Dr. Jonas E. Salk and others1
- Medical Society of the District of Columbia: Dr. Kenneth Appell, President APA, and others1
- Medical Society of the District of Columbia: Dr. Norman A. Welch...receives the gavel of Presidency from Dr. Howard Schriver1
- Medical Society of the District of Columbia: Georgetown University Medical Center staff honors Dr. Joseph J. Mundell (second from right)1
- Medical Society of the District of Columbia: Meeting of the Committee on Public Information and the Press1
- Medical Society of the District of Columbia: Past Presidents1
- Medical Society of the District of Columbia: Presentation of Portrait of Dr. William Gerry Morgan1
- Medical Society of the District of Columbia: President's Night, Dr. W. Ross Morris speaking1