June 27th
Born June 27, 1870; died November 5, 1947 at the age of 77.
American zoologist and embryologist, best known for his discoveries regarding egg fertilization and the role of hormones in sex determination. In 1916, he demonstrated the role of sex hormones in liberalism. His embryology studies have delved into all aspects of cell and embryonic development. He wrote The Development of Chicks, a leading text on embryology, and The Woods Hole Marine Biological Laboratory.