be made optional rather than obligatory. In other words, the movement was not in the direction of opposing laboratory work in science, but in the direction of the extension of the elective system. He therefore desires this correction to be made.
The entertainments called the Urania Spectacles that have been given in New York and Boston during the past two winters are very successful efforts to exhibit some of the wonders of science to large audiences. They consist of numerous photo-opticon views, in which coloring and motion as well as form are shown, accompanied by an explanatory lecture. The lecturer is Mr. Garrett P. Serviss, whose ability to make the facts of astronomy interesting is well known to the readers of the Monthly. The spectacles are now three in number: A Trip to the Moon, The Seven Ages of our World, and The Wonders of America. Among the more striking pictures in the first of these are an eclipse of the sun, close views of lunar craters and canons, and the rotating earth as it would be seen from the moon. In the second the progress of a world from a nebula to a burned-out cinder is traced; and in the last the marvelous scenery of our own land is depicted.
A specimen of volcanic dust from near Omaha, Nebraska, is described by Prof. J. E. Todd. It was from a stratum of whitish aspect, about eighteen inches in thickness, found in the bluffs facing the Missouri River. It has the same general characteristics as the volcanic dust which has been found in quantity along the Republican River, in southern Nebraska, and in Knox, Cumming, and Seward Counties in the same State; but it differs in being stained with oxide of iron and the sharp angular grains coated with carbonate of lime. This locality is the most eastern exposure of the volcanic dust stratum which is found scattered over the most of Nebraska.
The summer school has now been made an integral part of the university at Cornell, and will be open for 1893 with courses considerably enlarged in scope. Without excluding others qualified to take up the work, these courses are offered for the special benefit of teachers. They are open to women as well as to men, and the same facilities for work are afforded to those students as to the regular students of the university. Every opportunity will also be afforded for original research. Addresses will be delivered similar to those given in 1892 by President Schurmann and ex-President White. The session will continue from July 6th till August 16th.
The sixth session of the Marine Biological Laboratory, Woods Holl, Massachusetts, will begin June 2st and continue till August 30th. The Laboratory for Investigators will be open during the whole time, and in it twenty special tables will be provided for those who are prepared to begin original work. An elementary course in vertebrate embryology will be introduced, with studies mainly of the fish-egg, conducted by Mr. Lillie and Prof. Whitman, to open July 5th and continue six weeks. The Zoölogical Laboratory for Teachers and Students will be open during the same time, with regular courses in zoölogy and microscopical technique, in which students will be permitted, under special conditions, to begin their individual work as early as June 15th. The Botanical Laboratory will be opened July 5th for study of the structure and development of types of the various orders of cryptogamic plants, giving special attention to the marine algae. A department of laboratory supply has been established, to fill orders from a distance, in which a considerable number of species are kept in stock. The laboratory is under the general direction of Prof. C. O. Whitman, with whom are eleven professors in special branches, and other assistants.
The opinion expressed by Mr. Alfred G. Mayer, in his article on the Habits of the Garter Snake, published in the Monthly for February, that snakes, as feeders on frogs and toads, are therefore friends of insects and indirectly enemies of leaves, is criticised by Garden and Forest as a dangerous generalization, "for, although the snakes will eat frogs and toads, as well as anything else in the line of small animals that they can master, they also eat a great many insects, and they could not, under any circumstances, in justice, be called protectors of insects."
The valuable memoirs of T. A. Conrad on the Tertiary fossils of the United States have become very rare, and are practically out of the market. Yet the work is of great importance to students. The idea of reprinting the work has accordingly found favor. A reprint of the volume on the Eocene is contemplated by Mr. Gilbert D. Harris, of the Smithsonian Institution; and the Wagner Free Institute of Science, of Philadelphia, proposes to reprint the volume on the Miocene—the Medial Tertiary—with photogravure reproductions of the original plates and an introductory chapter and a table showing the present state of the nomenclature of the species; the whole forming an octavo volume of about 150 pages, with 49 plates. Subscriptions are asked for 100 copies, at $3.50 each.
Mr. Joseph E. Carne, Curator of the Mining and Geological Museum at Sydney, Australia, has been appointed a geological surveyor.
Researches into the conditions of the life of micro-organisms have shown them to be variously adapted to considerable diversities of temperature, and some of them to be adapted to great ranges. Forster and Bleekrode have found a few species containing