Major James Carroll (June 5, 1854 – September 16, 1907) was a US Army physician. Carroll was born in England. He moved to Canada in 1874, and enlisted in the U.S. Army in 1874. He graduated with an M.D. from the University of Maryland in 1891. After graduating Carroll studied bacteriology under Dr. William H. Welch at Johns Hopkins Hospital and assisted Walter Reed in pathology laboratories. Carroll and Reed later worked together at the Army Medical Museum in Washington and the Columbia University Medical School. In 1900 he served as an American physician and a member of the Yellow Fever Commission in Cuba, along with Walter Reed, Jesse William Lazear, and Aristides Agramonte. He and Lazear subjected themselves to the bite of infectious mosquitoes to test the theory that mosquitoes were ca