July 9th
Born July 9, 1831; died May 1, 1904 at the age of 72.
Wilhelm His, born in Basel, Switzerland, was a German anatomist and embryologist who created the science of tissue formation, or the study of embryonic origin of different types of animal tissues. His discovery, in 1886, that each nerve fiber originates from a single neuron was essential to the development of neuronal theory. With it, he can examine the embryo. He was the first to accurately describe the human embryo.