Wilhelm His Jr.

Wilhelm His Jr. (1863 to 1934) was a Swiss cardiologist and anatomist, the son of the anatomist Wilhelm His Sr. In 1893 he discovered the bundle of His, the collection of specialized cardiac muscle cells that carries electrical impulses through the heart and helps synchronize the contraction of the heart muscle. Later in his career he was a professor of medicine at the University of Berlin, where he was among the first to recognize that the heartbeat has its origin in the individual cells of heart muscle. His name survives in several medical eponyms: Werner-His disease, another name for trench fever, and the angle of His, also called the incisura cardiaca, which was named after him by Daniel John Cunningham in 1906.