Harrison, Ross G.

Harrison, Ross G. (Granville)

(1870–1959) developmental biologist; born in Germantown (Philadelphia), Pa. He taught at Bryn Mawr College (1894–95), then joined Johns Hopkins (1886–1907). He moved to Yale (1902–38, emeritus 1938–59), then became chairman of the National Research Council (1938–46). He performed extensive transplantation experiments in frog embryos to investigate nerve fiber development (1897–1910). He devised the hanging drop microscopy technique to observe living cells (1907). In the same year he demonstrated that nerve cells cultured outside the body will undergo normal differentiation, thus proving that the cell is the fundamental developmental unit of the multicellular organism. He designed elegant experiments using salamander larvae to demonstrate interspecific grafting, and also investigated eye development, the embryological implications of the neural crest, and alterations of limb symmetry. He was a calm and judicious person, who, after his retirement, served on many scientific and academic committees, and was acclaimed as a visiting lecturer.