A very interesting Bulletin of eight pages on the Chrysanthemum Rust has been issued by J. C. Arthur, botanist of the Indiana Agricultural Experiment Station. It is No. 85, and is dated October, 1900. Dr. Arthur gives a general account of Uredineae or Rusts, explaining that the typical forms have three prominent sets of spores, namely (1) aecidiospores, usually red or orange in little white cups, (2) uredospores, generally of a rusty yellow color and abundant (hence the group name, Rusts), and (3) teleutospores, or the Winter spores, usually dark brown or black. He further states that only uredospores have yet been found in Europe and America, and since the fungus is an annual, it is puzzling to see how it escapes extermination in winter and spring when Chrysanthemum plants are latent. The assumption that this was the well known and common Puccinia hieracii or Puccinia tanaceti he proves to be incorrect by inoculation experiments. Uredospores from Chrysanthemums he sowed on Chrysanthemums and obtained a crop of uredospores. Similar uredospores sowed on Dandelion, Burdock, and Ox-eye Daisy produced no infection; uredospores from the latter hosts sown on Chrysanthemum likewise produced no infection. Uredospores from Dandelion sown on Dandelion produced uredospores. Others have tried similar experiments, using Tansy, Costmary, Orange Hawkweed, Giant Daisy, and Marguerite, besides the host plants named above, but the Chrysanthemum Rust refuses to grow on any of them. This Rust, which is common and well known on the Chrysanthemum in Japan, has been named Puccinia chrysanthemi by Rose. In connection with suggestions relative to combating the disease, Dr. Arthur says that “so long as the teleutospores do not make an appearance in this country, the careful cultivator may feel assured that a moderate amount of timely effort will enable him to rid his establishment of the Rust, if he is so unfortunate as to have it donated to him by some careless florist. Observations made by the writer and others show that the tendency is for the disease to disappear of itself, to run its course in an establishment and die out, which is very likely to some extent due to the absence of teleutospores.” BRYOLOGY.—Mrs. Britton’s popular articles on the Mosses and how to study them, that have appeared from time to time, furnished the directions and incentive to many who before had taken little or no interest in this group of plants. Her purpose and plan are imitated and extended in a charming little book, that has been prepared and published by Dr. A. J. Grout, of the Boys’ High School, Brooklyn, New York, called “Mosses with a Hand-Lens.” The author says that many years of study of Mosses in the field and in Herbaria have convinced him that “any person of average intelligence can easily learn to recognize seventy to one hundred common mosses, with the aid of a hand-lens of ten to fifteen diameters magnifying power.” [Illustration: Fig. 9, Ceratodon.]