Light is necessary for the formation of food substances by green plants, and it is an important factor in distribution in land and marine forms. Growth and reproduction are generally retarded by the action of the blue-violet rays. Light is fatal to certain bacteria and other low forms of vegetable life. Many plants have the power of accelerated growth of stems in diminished light as an adaptation for lifting the leaves above "shading" objects. The growth of many leaves and of the perianth of flowers is hindered in diminished light. The outward form of many organs, particularly leaves, is dependent upon the intensity of the light received. The internal structure of bilateral or dorsiventral organs is largely determined by the direction of the rays. Plants have the power of movement to adjust their surfaces to a proper angle with impinging light rays, as a protective adaptation. * * * * * Matches which do not contain any phosphorus and which take fire by friction on any surface--a match that has been long sought--have been prepared by Mr. S. A. Rosenthal and Dr. S. J. von Kornocki. It is represented that they can be manufactured as cheaply as ordinary matches. THE STONE AGE IN EGYPT. BY J. DE MORGAN. The investigation of the origin of man in Egypt is a very complex problem, belonging as much to geology as to archæology. The earliest evidences we have of human industry, in fact, go back to so remote a period that they should be regarded rather as fossils than as archæological documents. They are very coarsely worked flints, which are found near the surface of the ground among the pebbles of the Quaternary or Pleistocene epoch, and similar to those which occur abundantly in Europe, America, and Asia; but the study and collection of them have been pursued with less method than in those countries. The more recent monuments, so much more conspicuous and more easily accessible, have attracted most attention, while these have been left in the background.