Gunnar Degelius, born in Uppsala in 1903, is the Grand Old Man of Swedish, and indeed of World Lichenology. I presume that many of you are familiar with his work.
Degelius’ thesis on oceanic lichens, defended in 1935, is a classic and typical of his approach to lichenology, with meticulous treatments of taxonomy, nomenclature and ecology. In 1936 Degelius’ first paper on Collema appeared. It was a prelude to what became a life-long interest in the group. His outstanding monograph on this notoriously difficult genus in Europe appeared in 1954, and was followed by a revision of extra-European taxa twenty years later.
Floristic studies are another interest of Degelius. An early example is the flora of Angermanland from 1931, which was followed by similar surveys of Norra Skafton, Orno and other parts of Sweden as well as North America, Iceland, The Azores and more recently the islands of Vega and Anholt. Although Degelius is best known for his taxonomic and floristic studies, it should not be forgotten that he has also made important contributions to the ecology and biology of lichens. A peculiar type of diaspores, “lichenized hormocysts”, is one of his discoveries. Most valuable are perhaps Degelius’ two papers on the succession of lichens on twigs, using the yearly growth of the branches to date the settlement of lichens.
Generosity and encouragement, particularly to young lichenologists, is one of his characteristic features. His wide knowledge has inspired and assisted scientists in many countries. He has travelled widely and built up a large herbarium. His marvelous library is scarcely surpassed anywhere.
Over the years, Degelius has published about 120 papers, mostly on lichens. His first scientific study, on Arthonia spadicea, appeared in 1923. I know that he now has a manuscript on new Collema species in preparation, and that he plans to take up SEM-studies of Collema spores. The Acharius Medal is an adequate homage to an outstanding contribution to lichenology spanning seventy years. We wish him all the very best in his present and future endeavors.
– Lars Arvidsson