P.Karst.

Petter Adolf Karsten (16 February 1834 – 22 March 1917) was a Finnish mycologist, the foremost expert on the fungi of Finland in his day, and known in consequence as the "father of Finnish mycology".

Karsten was born in Merimasku near Turku, studied at the University of Helsinki, and then moved to the inland of Tammela, where he spent most of his life with teaching botany and doing research at the Mustiala Agriculture Institute (now the Faculty of Agriculture of the HAMK University of Applied Sciences).

He amassed a vast collection, both by his own efforts and those of his correspondents, and named about 200 new genera and 2,000 new species. In his mycological studies he extensively used the microscope and can be considered as the pioneer of fungal microscopy. Karstenia, the international journal of mycology published by the Finnish Mycological Society, is dedicated to Karsten.

...
Wikipedia