Clues for the determination of the spore-sizes in Boudie’s illustrated publications

A scale communicated in a letter written by Boudier makes possible the establishment of the spore-sizes in his earlier publications; it is here reproduced. Similarly, but with a different scale, the sizes of the spores in Boudier’s publications from 1885 onwards can be revaluated. His microscopic measurements have been found to be usually about 10 % too high.