See also: 1640 in science, other events of 1641, 1642 in science and the list of years in science.
Births Nehemiah Grew, English botanist and physician who made some of the early microscopical observations of plants (died 1712) Regnier de Graaf, Dutch physician and anatomist who discovered the ovarian follicles, which were later named Graafian follicles (died 1673) Deaths January 3 - Jeremiah Horrocks, English astronomer (born c1617)
