Page:Popular Science Monthly Volume 7.djvu/729

Rh the weeds of America, and a large proportion of her worst insect pests, including two beetles, viz., the asparagus-beetle (Crioceris asparagi) and the elm-leaf beetle (Galeruca calmariensis), in the very same family as our doriphora, have been imported from Europe, there would seem poor foundation for such an argument. Moreover, a number of other insects—among them some beetles—of less importance, may be included in the number of importations; and the rape-butterfly (Pieris rapæ), whose progress westward has been simultaneous with that of the doryphora eastward, and whose importation dates back but a few years, bears witness to the fact that insects more delicate, and with fewer chances of safe transport than doryphora may succeed in getting alive from one country to the other, and in gaining a foothold in a new home. The ravages of the insect, bad as they are, very naturally get exaggerated at such a distance from its native home, and the following from an English gardening periodical gives altogether a too gloomy picture: 'When once a field of potatoes has been attacked, all hopes of a harvest must be given up; in a few days it is changed into an arid waste, a mere mass of dried stalks.' It should not be forgotten that the American cultivator, by means of intelligence and a little Paris-green, is pretty much master of the doryphora. It is to be hoped that this exposition of the facts and probabilities of the case will put people on their guard, and cause intelligent action to be taken to prevent the importation of so dangerous a pest as this potato-beetle.—The Garden.



URING the months of March and April a spirited discussion took place in the Académie de Médicine, at Paris, on fermentation and kindred subjects, in the course of which M. Pasteur was called upon again to sustain and develop his theory of this process, which is now so generally accepted. His share in the discussion was marked by the brilliancy of exposition and accuracy of experiment which have made him perhaps the most formidable debater among our modern savants. We have not here the space to speak of the certainty with which he seizes upon the central point of the discussion, and the tenacity with which he clings to it, the rapidity with which he exposes the weak points of an adversary's argument, and the absolute confidence shared even by his bitterest opponents in the accuracy of his experiments and statements. What now follows is the 