Page:Popular Science Monthly Volume 50.djvu/886

864 exhibit as much variety as we are accustomed to find on land. Detailed charts will be made to show the variations that take place from point to point. Such investigations of the kind as have been made heretofore have had regard chiefly to the fishes, while comparatively little attention has been paid to the other features.



To the Editor.

I beg leave to call your attention to a mistake in my article on The Malarial Parasite, which I regret to say must have been in the original manuscript and which escaped me when reading the proof. On page 685, thirteenth line from the top, the word "quartan" should have been "tertian." It is evident that when a daily paroxysm occurs this is due to the alternate development of two groups of tertian parasites, in which the cycle of development is forty-eight hours, and net to two groups of quartan parasites, the cycle of development of which would be seventy-two hours.

2em

summer lectures in botany of the Torrey Botanical Club and the College of Pharmacy of the City of New York will be given at the college, 115 West 65th Street, in two weekly courses: the first, on the General Morphology of Plants, Fridays, at 4, by W. Arthur Bastedo, beginning March 26th and closing June 11th; and the second course, on the Summary of Cryptogamic Botany, with practical work on the microscope, Thursday evenings, by Dr. Smith Ely Jelliffe, March 25th to June 10th. The prices of tickets are $5 to the first course and $10 to the second course. The eight Saturday excursions (stormy Saturdays excepted) will begin April 24th. Tickets for either course may be obtained now at the college.

American trout—"rainbow trout" as the French call it—is found by M. Hugues Oltramare to be of very much more rapid growth than either the European lake or river species, and therefore presumably a more profitable kind to raise. The fry of the species of the same age are very readily distinguished by the superior size of the Americans. The latter are also more active, more constantly in motion, and eat more.

results of experiments made some time ago by Dr. Lösener on the effect of the conditions of burial on the microbes and germs of disease are reassuring. Infected carcasses were buried under conditions like those of ordinary burials. The duration of the vitality of the pathogenic organisms was various, but all were dead within a year except the anthrax bacilli, which retained their full complement of virulence during the whole period. None of the organisms either, except those of anthrax, found their way to the adjacent soil and water; but so admirable a barrier is provided by the soil that the earth close beneath the bottom of the hole containing the infected carcass was in every case found quite devoid of pathogenic germs. Experiments made in Massachusetts with sewage have shown that filtration through soil is effective to purify from bacteria.

deposits of volcanic ash in Nebraska are described by Prof. Rollin D. Salisbury in Science: at Ingham, Edison, and Orleans. At all these places several more or less associated exposures of the ash appear; and in all the cases it is found in the side or near the head of a cañonlike ravine. It varies in color from white to yellow cream or light gray, and in grain from the grade of coarse sand to that of white flour. In some places the bed is more than twenty feet thick. Such ash has been found in other places in Nebraska, and it has already become an important article of commerce, under the name of pumice.

has continued with success the method, which he began in 1861, of discovering new minor planets by the small shift of their images, due to orbital motion, on a photographic plate exposed behind a large portrait lens. Since 1890, Prof. Wolf has discovered fifty-six new planets, of which thirteen were found in 1896. The whole number of small planets which have been calculated is now four hundred and twenty-two.

breed of fowl has been systematically created in France by a M. Gourgaud—dwarfs of the breed called there Gâtinais, or gâtinais bantams. Associating with a gâtinais hen an ordinary white double-crested bantam cock with blue toes, M. Gourgaud obtained a nest of half-dwarf chickens having single crests and double crests, and some blue and others rosy toes. He then went to work to eliminate the double crests and blue toes, directing the association of pairs to that ideal, and approaching it more nearly with each successive generation. In 1895 he had obtained a fixed dwarf breed, with rosy toes and single crests.

primitive relations between Europe and the East Mediterranean countries were a prominent subject of discussion in the Anthropological Section of the British Association. The sectional presidential address of Mr. Arthur J. Evans related to it, and papers bearing upon it were read by Dr. Montelius. Prof. Petrie, Mr. J. L. Myres, and others.