Presidential Address - Two Centuries of North American Lichenology

Surely no apology is in order for offering here an address in which attention is directed for the short time to a limited field in one of the biological sciences. All men of science are interested to some extent in the history of the rise and progress of every phase of scientific inquiry, and even for the layman who may favor us with his presence this evening, it is hoped that the record of devotion, sacrifice and completion of valuable work will afford something of interest