Astronomy Giovanni Schiaparelli realizee that meteor streams occur when the Earth passes through the orbit of a comet that has left debris along its path. William Huggins studied the spectrum of a nova and discovers that it is surrounded by a cloud of hydrogen. Biology Gregor Mendel published his laws of inheritance. Ernst Haeckel challanged the plant/animal division of life, observing that single celled organisms, the protists, do not fit into either category. Frederick Smith first discovers Formica candida in the Bournemouth, England, describing it as Formica gagates. Chemistry Dynamite invented by Alfred Nobel. Augustus von Hofmann proposed the now standard system of hydrocarbon nomenclature. Medicine Max Schultze discovers two sorts of 'receptors' in the retina. Awards Wollaston Medal for Geology: Charles Lyell Births Thomas Hunt Morgan, biologist, Nobellaureate in Physiology or Medicine Robert Broom, paleontologist. Deaths Bernhard Riemann, mathematician