Page:Popular Science Monthly Volume 20.djvu/444

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of the phylloxera and its eggs. From them he has found that the application of the acid, in the proportion of fifty cubic centimetres of the liquid acid to one cubic metre of air, is sufficient to kill all the phylloxera and eggs in a closed box in two hours; that the same effects may be obtained immediately in the open air by sprinkling the box with fifty cubic centimetres of the acid to one square metre of surface; that confinement for a few minutes with the former proportion of acid is sufficient to kill the phylloxera and soft insects of an analogous nature and their eggs, and purely herbaceous plants, while dry seeds exposed to it retain their germinative powers; and that its application is equally efficacious against the parasites in museums, while it does not harm the specimens which they infest. Plants and insects of a moist texture are the more readily affected by the acid. A high temperature is favorable to the operation by promoting the diffusion of the acid gas; a moist atmosphere is against it, by its tendency to hold the gas in solution. The application of the anhydrous acid has advantages over that of burning sulphur in that it can be made where sulphur can not be burned, is safer, and more convenient.



The President of the Entomological Section of the American Association stated, in his address at the meeting of the section, that while there were not known to be more than ten or twelve working entomologists in the country forty years ago, four hundred and thirty-six names were reported in last year's "Naturalists' Directory" of persons designated as entomologists. No other distinct branch of natural history except geology and botany has so many representatives in that book. The various journals of the last year contained three hundred and thirty-six contributions to entomology exclusively by Americans, the work of eighty writers.

The appointment of M. Wurtz, President of the Academy of Science, to be life-Senator, raises the number of members of the Academy belonging to the Upper House of the French Legislature to three, the two other members being M. Robin and M. Dupuy de Lome. The election of M. Berthelot, which is considered certain, will give the Academy a fourth representative in this body.

Mr. F. W. Putnam has exhibited to the Boston Society of Natural History specimens of a collection of several hundred rude stone implements which Mr. David Dodge has obtained from plowed gravelly fields at Wakefield, Massachusetts. The implements had not yet been found in place in the gravel, so that it was not possible to decide that they were true palæolithic implements; for rude forms of the same character are often associated in this country with finely polished implements of the Neolithic period. Some of the specimens were obtained from a very old pile of stone-chips nearly buried in the side of a hill, where similar implements to those found in the fields near by had evidently been made. It was worthy of remark that none of the arrow-heads and similar forms, common near places where palæolithic objects have been discovered, had been found in connection with these implements.

In a pamphlet on "The Discipline of the School," published by the Bureau of Education, Dr. Hiram Orcutt gives as the elements of school discipline, each of which he discusses under its special head: thorough organization and classification; the establishment of the authority of the teacher; work; a sound public opinion in the school; mental and physical recreation (gymnastics and exercise); kindness; power to punish, with wise discrimination, and courage to inflict punishment when it is required; regular systematic study and recitation; and good manners, which are inseparable from good morals.

Professor Cyrus Thomas has made a study of the Mexican manuscript called the "Manuscript Troano," which was discovered by the Abbe Brasseur de Bourbourg in 1865, and has concluded that it is a genuine Maya document; that it is a religious calendar of some kind, in which the day-characters are used for the purpose of designating the days and not for the signification of the words; and that it confirms the substantial correctness of Landa's characters for the day. He has begun the attempt to decipher the hieroglyphics of the text.

The yucca seldom perfects its seed in the United States. The failure is believed by Professor Riley to be in consequence of the flower depending for its pollination upon the office of an insect which has not yet been introduced to an extent corresponding with the diffusion of the plant. In his paper on "The Pollination of Yucca," before the American Association, Professor Riley describes some insects which he has found in or about the plant, by the agency of one or more of which he thinks the pollination may be accomplished in the rare cases where it is observed to occur.