Bayliss, Sir William Maddock
Sir William Maddock Bayliss (bā´lĬs), 1860–1924, English physiologist. At University College, London, he investigated the mechanism of heart action, circulation, and digestion. With E. H. Starling he discovered, in 1902, secretin, a hormone produced in the small intestine, and developed a theory of hormone action. He wrote Principles of General Physiology (1914) and The Vaso-Motor System (1923).