=Popular Co-operation in Health Work.=--In a review of A Quarter Century of Public Health Work in Michigan, Mr. Theodore R. MacClure, chief clerk of the State Board of Health office, says that experience in the State has indicated that it is necessary to have the co-operation of the people if the dangerous communicable diseases are to be restricted and prevented. In order to accomplish this result, the State Board of Health has published leaflets relating to the modes of spreading and the best methods for the restriction and prevention of such diseases. These leaflets have been printed by tens of thousands, and whenever a dangerous disease is reported to the central office several copies of the leaflet relating to the disease in question are usually sent to the local health officer. He is requested to place one of these instructive publications with the family where the disease exists, and a copy with each neighbor of the infected premises. The instruction comes at a time when people are interested to know about the disease in question, and in this way their general co-operation is sought and secured. Citizens are thus educated and become familiar with their duties in the premises, are taught wherein the dangers lie and how to avoid them, and are prompted by the strongest considerations to do their part in the matter. =Death of Prof. Oliver Marcy.=--Dr. Oliver Marcy, professor of natural science in Northwestern University, who died February 19th, in the eightieth year of his age, was a native of Coleraine, Massachusetts; was graduated from Wesleyan University in 1846, became teacher of mathematics in Wilbraham Academy, Massachusetts, and later professor of geology, etc., in that institution. In 1862 he was appointed professor of geology in Northwestern University, Evanston, Illinois, but taught in addition, at times, other branches of science and even some branches in other lines. He was twice acting president of the university. In conjunction with Prof. Alexander Winchell, he prepared a monograph on Fossils from the Niagara Limestone of Chicago, which was read to the Boston Society of Natural History. In 1866 he was naturalist to a Government expedition to the Bitter Root Mountains in Idaho and Montana, in which he collected scientific material, and of which he published an account in 1867. He wrote papers concerning the geology of the shore of Lake Michigan and of the region about Chicago; brought two fossil trees found in the university grounds to scientific notice; and contributed considerably to geological publications. He was curator to the natural history collection of his university for nearly thirty years. Two fossil species and a mountain in Montana have been named after him.