Page:Popular Science Monthly Volume 49.djvu/595

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the formation of cliffs are the same process. Sometimes the waves pile up a bank of sand or shingle which protects the cliffs from the direct action of the breakers. The cliff, however, gives way under the actions of wind, rain, and frost; and the material carried down to the base of the cliff by these agencies is removed by the Bea, so that the cliff is maintained at an angle steeper than the angle of repose, and is constantly falling. When the jointing lines of a rocky cliff slope downward from the shore line, the waves undermine the cliff, and great masses of superincumbent rock fall by their own weight, as the masses of coal fall in the mine through the skillful undercutting of the collier.

Mr. A. H. Thayer has an article in a recent issue of The Auk entitled The Law which underlies Protective Coloration. In it he sets forth "a beautiful law of Nature which, so far as I can discover, has never been pointed out in print. It is the law of gradation in the coloring of animals, and is responsible for most of the phenomena of protective coloration except those properly called mimicry. Mimicry makes an animal appear to be some other thing, whereas this newly discovered law makes him cease to appear to exist at all. The newly discovered law may be stated thus: Animals are painted by Nature darkest on those parts which tend to be most lighted by the sky's light, and vice versa" The author's theory seems to be that Nature, by a careful coloration, effaces the ordinary lights and shadows by means of which a solid body is recognized, and that the various markings which at first sight seem unnecessary are really for the purpose of forming a background such as one might see if the animal were transparent.

A curious instance of protective mimicry combined with intelligence is found in the nest of the dabchick, which, as described by Mr. Harry F. Witherby, is simply a mass of green floating weed common in streams and ponds, like other masses of the same weed, except that it may be a little higher and more compact, but not sufficiently so to enable one to distinguish it. When the white eggs have been laid in it, means of concealment are called for, which the bird provides by covering up the eggs with leaves when it goes away, thus transforming the nest again into apparently nothing more than a floating mass of weed. In a few days the eggs become so covered with dirt that they are exactly of the color of the nest, and do not need even this protection any longer.

The results reached in the report to the London Metropolitan Asylums Board on the use of antitoxine in diphtheria agree substantially with those recorded by observers in various other countries and confirm the favorable opinions. The general reduction in mortality obtained in the metropolitan fever hospitals is less than that claimed in some foreign institutions, but then, the London Times suggests, "there was less room for improvement in the former." In the more dangerous class of cases, and especially in those which came under treatment at an early stage of the disease, the drug fully maintained its reputation. These conclusions were unanimously concurred in by the six medical superintendents constituting the commission of inquiry.

The Third International Congress of Psychology will be held at Munich, August 4 to 7, 1896. All psychologists and all educated persons desiring to further the progress of psychology and to foster personal relations among students of the subject in different nations are invited to take part in the meetings—in which women will enjoy equal consideration with men. German, French, English, and Italian will be the languages used. The programme of the work in the congress is arranged under the general headings of psychophysiology, psychology of the normal individual, psychopathology, and comparative psychology; while the subheadings suggest an extensive range and variety of topics. The subscription price for membership in the congress is fifteen shillings, twenty francs, or about four dollars. Persons intending to present papers—twenty minutes in length—should give due notice of the same, before the beginning of the congress, to the secretary. Dr. Freiherr von Schrenk-Notzing, Munich, Max Josephstrasse, 2.

The growing of flowers to be put into the market as cut flowers has become an important business, and many large gardens are devoted to it in the vicinity of New York.