Harrison, Ross G(ranville) (1870–1959)

US developmental biologist. He performed extensive transplantation experiments in frog embryos to investigate nerve fibre 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.

Harrison was born in Germantown, Philadelphia, Pennsylvania. He taught at Bryn Mawr College (1894–95), then joined Johns Hopkins University (1886–1907). He moved to Yale University (1902–38) where he became emeritus professor (1938–59). Harrison was chairman of the National Research Council (1938–46). 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.