OBITUARY. 



NATHANAEL PRINGSHEIM. 

 Born 1823. Died 1894. 



THIS famous German botanist, whose death was recorded in our 

 last number, was born in 1823 at Wziesko, in Upper Silesia. 

 Starting as a medical student in the University of his native province, 

 he afterwards went to Leipzig, and later to Berlin. In the mean- 

 time, however, he decided to devote himself to botany, and it was a 

 botanical thesis in which liis Ph.D. was gained at Berlin. After 

 taking his degree he visited Paris, and on his return commenced his 

 career, in 1851, at Berlin University. Five years after, at the age of 

 33, he was elected Member of the Berlin Academy of Sciences. In 

 1864 he was called to Jena to replace Schleiden as ordinary Pro- 

 fessor, an appointment he held for four years. During his stay in 

 Jena he founded an Institute of Plant-Pliysiology, the first of its kind. 

 The idea took, similar laboratories were established at other Univer- 

 sities and agricultural high-schools, and a tremendous impetus was 

 given to the study of plant-physiology. In 1868 Pringsheim returned 

 to Berlin, but did not join the teaching staff of the University. From 

 his own resources he founded a botanical laboratory, and soon 

 established a school, to which belonged Strasburger, Tschirch, 

 Vochting, and other well-known botanists. 



Pringsheim's great work was on the sexual relations in Cryp- 

 togams, especially Algse, following up the results of Thuret and 

 others. In a series of researches on the history of growth in 

 individual families, he showed the existence in the Algae of 

 widely different forms of sexuality and development. Another 

 subject attacked by Pringsheim was Chlorophyll. He was the 

 first to demonstrate the true relation between the green colouring 

 matter and the protoplasmic corpuscle ; as to the function of 

 chlorophyll, he held a view the reverse of that generally accepted, 

 namely, that the colour acts as a shade, absorbing those rays of light 

 which promote destructive metabolism, and thus making possible the 

 constructive process. 



A biographical notice would be incomplete without mention of 

 the familiar " Jahrbiicherfiir wissenschaftliche Botanik," started in 

 1857 and continued up to the present. Pringsheim was one of the 

 oldest foreign members of the Linnean Society, having been elected 

 on May 3, 1866. 



