Two Books on Lichens. The Lichens of Minnesota. By Bruce Fink. Pp. xvii, 269, 51 pl. 18 figs. Washington, 1910. Die Brandpilz der Schweiz. By Prof. Dr. H. C. Schellenberg. Pp. xlv, 180, 79 figs. Price, 6 m. 40 pfg. Bern, 1911.