THE GOMBI ARROW POISON.—In a recent number of the Bulletin Mensuel de la Société á Acclimatation of Paris, M. M. E. Hardy gives a detailed account of researches and experiments on the active principle of the poison obtained from the seeds of Strophanthus hispidus. This plant, which belongs to the poisonous order Apocynaceæ, was first observed by Houdetot, a French naturalist in Sene-gambia, afterwards by Smeathmann near Sierra Leone, by Baikie at Nupé, by Griffon du Bellay at Gaboon, and by Gustav Mann in Western Tropical Africa. It is a climber with a hollow cylindrical stem, and grows in the forests, where it ascends to the summits of the highest trees. The oblong, nearly sessile, opposite leaves are from ten to twelve centimetres long by five wide, and are covered with hairs, particularly on the under surface. The yellow flowers are borne on terminal cymes. The fruit is a cylindrical follicle somewhat thicker that the thumb, and contains from 100 to 200 oval seeds. By means of a fruit given them by the Paris Society, MM. Hardy and Gallois have discovered that the active principle is not, as was supposed, an alkaloid, and for it the name Strophantine, given to it some years ago by Dr. Fraser, is retained. Besides, they succeeded in isolating a substance presenting the characters of an alkaloid, but which did not seem to possess any marked physiological properties; for this they propose the name Inéine. The former is very poisonous, a single crystal placed under the skin of a frog's foot causing the cessation of the heart's action in a few moments. Even after this has taken place the animal still possesses the power of motion, and it is only after respiration has become impossible, owing to the interruption of circulation in the nervous centres, that death ensues from paralysis of the heart. These observations, though yet incomplete, accord pretty well with facts recorded by different authors, and seem to prove that Strophantine is really the poisonous agent in Strophanthus hispidus. The most elaborate experiments on the poison found at the extremity of the arrows (used by the natives both in war and in hunting) are those conducted by MM. Carville and Polaillon in the laboratory of M. Vulpian. They were made on various classes of animals and show that the deadly action is much more rapid, in mammals and birds than in molluscs, crustaceans, and fishes. On frogs under the influence of curare the poison acts much more slowly, though the respective actions of the two substances do not neutralise each other.