Herbert William Conn (January 10, 1859 – April 18, 1917) was an American bacteriologist and educator. Born in Fitchburg, Massachusetts, the son of Reuben Rice Conn and Harriot Elizabeth, he became ill from rheumatic fever during his youth and had to be withdrawn from public school because of his poor health. Instead, he was educated at Cushing Academy, a private school in Ashburnham, Massachusetts, then matriculated to Boston University where he graduated second in his class with an A.B. in 1881. He entered graduate school at Johns Hopkins University in 1881, receiving his Ph.D. on animal morphology, physiology, and histology in 1884 with a thesis titled, "Life-history of Thalassema", for which he received a Walker prize from the Boston Society of Natural History. In August, 1885, he was m