The subject of the chemical constitution of matter was taken up by Mr. Johnstone Stoney, F. R. S., who amused and interested the chemical section by a number of drawings of tetrahedra, octahedra, etc., on to which he dexterously stuck representations of oxygen atoms, chlorine atoms, and so on. His general endeavor seemed to be to convince his auditors that in most basic salts oxygen is divalent, being in direct combination with the acidifying constituent of the molecule, but that when oxygen is not so directly related to this constituent in basic salts it is tetravalent. In the geological section, Dr. Bryce observed that there are two lines along which earthquakes are commonly observed in Scotland, the one running from Inverness, through the north of Ireland, to Galway bay, and the other passing east and west through Comrie. The phenomena of earthquakes in the latter district are now being systematically observed and recorded, under the direction of a committee appointed by the British Association, seismometers being employed on the two principles of vertical pendulum and delicately poised cylinders. Arrangements have been made to ascertain whether shocks in this region can be traced to any common central point, there being reason to believe them to be connected with a mass of granite in Glen Lednoch, whose position was indicated on a map exhibited by the author. He thought the Comrie earthquakes may be explained on Mr. Mallet's theory of a shock produced by the fall of huge masses of rock from the roof of huger caverns in the earth's crust. In a paper on the plants of the coal measures, Prof. W. C. Williamson expressed his strong conviction that the flora of the coal measures would ultimately become the battlefield on which the question of evolution with reference to the origin of species would be fought out. There would probably never be found another unbroken period of a duration equal to that of the coal measures. Further, the roots, seeds, and the whole reproductive structure of the coal-measure plants are all present in an unequalled state of preservation. With reference to calamites, Prof. Williamson said that what had formerly been regarded as such had turned out to be only casts in sand and mud of the pith of the true plant. He had lately obtained a specimen of calamite with the bark on which showed a nucleal cellular pith, surrounded by canals running lengthwise down the stem; outside of these canals wedges of true vascular structure; and lastly, a cellular bark. In the department of anthropology, Dr. Phené read a paper "On Recent Remains of Totemism in Scotland." He defined Totemism as a form of idolatry; a totem was either a living creature or a representation of one, mostly an animal, very seldom a man. It was considered, from reference to Pictish and other devices, that a dragon was a favorite representative among such people of Britain as had not been brought under Roman sway.