The formation of a large woody fruit, often in the shape of an urn, from which the top spontaneously separates in the form of a lid, is one of the characteristics of the order Lecythidaceæ, which includes the _Couronpita Guianensis_, or "cannon ball tree"; the gigantic _Lecythis ollaria_, or "monkey-pot tree," whose great woody pericarps serve as drinking vessels; and the _Lecythis Zabucajo_, whose fruit is known in the market as sapucaia nuts, and is greatly superior to the closely allied Brazil nuts as regards flavor and ease of digestion. All the trees of this order are natives of South America, and especially of Guiana. * * * * * THE ACTION OF THE MAGNET IN HYPNOSIS. Mr. Tamburini some time ago observed that, during a period of lethargy, the approach of a magnet produced in persons affected with hysterical hypnosis a series of modifications of the respiratory functions and of contractility. From some very careful experiments made by him and Mr. Righi in common, upon the lady who was the principal subject of his observations, it results that (1) it makes no difference whether the magnet be presented by its poles or its neutral line; (2) that any mass of metal whatever acts like a magnet; (3) that an electromagnet produces exactly the same effect whether it be or be not excited by a current; and (4) that a glass tube filled with cold or warm water likewise produces analogous effects, which disappear when the water is raised to the temperature of the human body. It seems, therefore, that the magnetic properties of the magnet count for nothing in the phenomena observed.--_Journal de Physique_. * * * * * THE SCIENTIFIC AMERICAN SUPPLEMENT. PUBLISHED WEEKLY. Terms of Subscription, $5 a Year. Sent by mail, postage prepaid, to subscribers in any part of the United States or Canada. Six dollars a year, sent, prepaid, to any foreign country. All the back numbers of THE SUPPLEMENT, from the commencement, January 1, 1876, can be had. Price, 10 cents each. All the back volumes of THE SUPPLEMENT can likewise be supplied. Two volumes are issued yearly. Price of each volume, $2.50, stitched in paper, or $3.50, bound in stiff covers. COMBINED RATES--One copy of SCIENTIFIC AMERICAN and one copy of SCIENTIFIC AMERICAN SUPPLEMENT, one year, postpaid, $7.00. A liberal discount to booksellers, news agents, and canvassers. MUNN & CO., Publishers, 361 Broadway, New York, N.Y. * * * * * PATENTS. In connection with the Scientific American, Messrs. MUNN & Co. are Solicitors of American and Foreign Patents, have had 39 years' experience, and now have the largest establishment in the world. Patents are obtained on the best terms.