PARISAcademy of Sciences, Aug. 24.-M. Bertrandin the chair. The following papers were read:-Ninth note on guano, by?.? Chevreul.-Study of the fossil grain found in a silicified state in the coal formation of Saint-Etienne. Second part: Description of genera, by Ad. Brongniart. The author describes Poly lopho sper mum, Codonospermttm, Stephanospermumy and sEtheotesta.- Note on the Central Sea of Algeria, by?. E. Roudaire. This is a reply to objections raised by MM. Fuchs and E. Cosson.-Researches on the effects of powder in firearms, by?. E. Sarrau.-On the passivity of iron; second note, by M. A. Renard.-Memoir on vegetable protoplasm, by M. Ganeau.-On some phenomena of localisation of mineral substances in the Articulata; physiological consequences of these facts, by?. E. Heckel. The author has been feeding insects with arsenic. The metallic powder was mixed with flour, and after repeated small doses the insects {Mantis religtosa, Blatta occidentalis, and Cerambyx /zeros) were killed and various parts of the intestinal tube examined. The Malpighian tubes only gave decided indications of arsenic.-Various communications on Phylloxera vastatrix were received from MM. Ador, Boutin, Rommier, Morlot, Barnier, and others.-On a new formula for obtaining by successive approximations the roots of an equation of which all the roots are real, by M. Laguerre.-On the direct combination of chromic acid with wool and silk; applications to the colouring and analysis of wines, by M. C. Jacquemin. M. C. Chevreul made some remarks on the foregoing paper.-On the ureides of pyruvic acid and its brominated derivatives, by M. E. Grimaux. Pyruvic acid heated with urea gives a substance of the formula C12H14N804. When excess of urea is employed the compound C10N16N8O7 is produced. With excess of acid another body is obtained, of which the composition has not yet been established. A nitro-body of the formula C12H10N8On has been prepared from these compounds, and likewise a ureide of tribrompyruvic acid of the formula C10H8Br6N8O6.-Analyses of various pieces of calf flesh, mutton, and pork sold in the Paris market in 1873 and 1874, by M. Ch. Mene.-Anaesthesia produced by the injection of chloral into the veins for the removal of a cancerous tumour, by M. Ore.-Application of the graphical method to the determination of the mechanism of rejection in rumination, by M. J. A. Toussaint.-Note on the physiological action of apo-morphine, by M. C. David. The author has experimented on dogs, cats, pigeons, rabbits, and guinea-pigs. The influence of various reagents on the alkaloid has also been studied.-Action of the sulphydric acid of the sources of the Luchon on granitic galleries, by M. F. Garrigou.-Observations of the Perseides made at the Observatory of Toulouse on August 5, 7, 8, and 9, 1874, by M. Gruey.-Observations made at Paris of the shooting stars of the month of August 1874; progress of the phemonenon from 1837 to 1874, by M. Chapelas.