BY the death on February 22 of Prof. Ludwig Jost, Germany has lost one of its most respected botanists and science one of the leading plant physiologists. Born in 1865 at Karlsruhe, he was educated at the local Gymnasium. In the autumn of 1883 he commenced his studies at the University of Heidelberg, attending particularly the lectures of Biitchli and Pfitzer. Afterwards he moved to Strassburg to study under de Bary. In 1887 he took his doctor's degree there, presenting a thesis on the breathing roots of palms. In the same year he was appointed assistant to Prof. Groebel in Marburg, and later returned to Strassburg, where he acted as assistant first to de Bary and after the death of the latter to Count Solms Laubach. In 1894 he was appointed assistant professor, and in 1907 to a full professorship in the University of Strassburg. In 1919, when the French re-entered that town, he had to leave, but was lucky enough to get an appointment to the vacant professorship at Heidelberg, which he held until his retirement in 1934. He was then elected emeritus professor and continued his scientific work privately *in the Kaiser Wilhelm Institute at Heidelberg, where he died, having been failing in health for some years. He was always strongly averse to the Nazi regime, and his sufferings were accentuated by the poor nutrition since the end of the War.