side of the quartz, thus exposing again the unusual faces. Some of the calcite layers are still present in the specimen. The new mineral lawsonite is more fully described by Ransome and Palache1 than was the case in the original paper by Ransome. The formula is H, Ca Al, Si,O,.-Walker" finds that the sperrylite from the Sudbury district probably occurs originally included in chalcopyrite. The new face (10.5.2) was observed. The suggestion is made that Os and Ir occur replacing Pt in sperrylite, and an analysis of the products of the Murray mine, showing the presence of these elements, is given. (If, as this analysis would indicate, the two elements osmium and iridium are present in an amount equal to one quarter that of the platinum, it is difficult to suppose that they exist in the sperrylite, since Wells states specifically that he found no iridium in the sperrylite analyzed by him).—Adams and Harrington' describe a new alkali-hornblende chemically near an orthosilicate, and a titaniferous andradite from the nepheline-syenite from Dungannon, Hastings Co., Ontario.-Merrill notes an occurrence of free gold in a black mica granite from Sonora, Mexico, apparently as an original constituent of the rock.-Crocoite crystals from Mt. Dundas, on the west coast of Tasmania, measured and figured by Palache" present, in addition to the twelve known forms the new, though doubtful, prism (10.3.0). GEOLOGY AND PALEONTOLOGY. Permian Land Vertebrata with Carapaces.- In the NATURALIST for 1895 (November) I described under the name of Dissorhophus a new genus of probably Ganocephalous Stegocephalia with an armadillo-like carapace. In the Proceedings of the American Philosoical Society for the same year and month I described a new family of Cotylosaurian Reptiles protected by a similar structure. These constitute the only forms of land vertebrates so constructed known from the paleozoic formations. The nearest approach to it previously known from the Permian is seen in the genus Zatrachys, where the 13 Zeitschr. f. Kryst., XXV, pp. 531-537, 1895. |
