CONTENTS. 



Number 237. 



Page 



Art. XXII. — Rocky Mountain Protaxis and the Post-Creta- 

 ceous Mountain-making along its course ; by J. D. Dana 181 

 XXIII. — The Magneto-optical Generation of Electricity ; by 



Samuel Sheldon — 196 



XXIV.— Contributions to Mineralogy, No. 49 ; by F. A. 



Genth, with Crystallographic Notes, by S. L. Penfield 199 

 XXV. — Chalcopyrite crystals from the French Creek Iron 



Mines, St. Peter, Chester Co., Pa. ; by S. L. Penfield. 207 

 XXVI. — Koninckina and related Genera; by Charles E. 



Beecher. (With Plate II) 211 



XXVII. — The effect of pressure on the electrical conductivity 



of liquids; by C. Barus 219 



XXVIII. — Notice of two new Iron Meteorites from Hamilton 



Co., Texas, and Puquios, Chili, S. A. ; by Edwin E. 



Howell 223 



XXIX.— The Cretaceous of Manitoba ; by J. B. Tyrrell 227 



XXX.— On Mordenite ; by Louis V. Pirsson 232 



XXXI. — Geology of Mon Louis Island, Mobile Bay ; by 



Daniel W. Langdon, Jr 237 



XXXII. — On Leptsenisca, a new genus of Brachiopod from 



the Lower Helderberg group ; by Charles E. Beecher. 



(With Plate IX) . 238 



XXXIII. — North American Species of Strophalosia ; by 



Charles E. Beecher. (With Plate IX) 240 



XXXIV. — Notes on the Microscopic Structure of Oolite, with 



analyses ; by Erwin H. Barbour and Joseph Torrey, 



Jr .... 246 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics. — On a new Element occurring in Tellurium, etc., Grun- 

 wald: On the Chlorides of the Compound Ammoniums; Le Bel, 250. — On the 

 production of Ozone and the formation of Nitrates in Combustion, Ilosvay, 251. 



Geology and Mineralogy. —Clinton Group fossils with special reference to Collec- 

 tions from Indiana, Tennessee and Georgia, Foerste, 252. — Presidential Ad- 

 dress before the Geological Society of London, Blanford, 254. — Paleozoic 

 Fishes of North America, Newberry, 255. — Chert-beds of the Lower Silurian 

 of Organic Origin, Hinde: Fossils in the Taconic limestone belt at the west 

 foot of the Taconic Range in Hillsdale, N. Y., Dwight, 256. — Revision of the 

 genus Araucarioxylon of Kraus, etc., Knowlton: Ueber dei Reste eines Brot- 

 fruchtbaums, etc , Nathorst: Tertiare Prlanzen derlnsel Neusibirien, Schmal- 

 hausex, 257. — La Flora dei Tun del Monte Somma, Meschinelli: Remarks on 

 some Fossil Remains considered as peculiar kinds of Marine Plants, Lesque- 

 reux: Brief notices of some recently described minerals, 258. — On the sup- 

 posed occurrence of Phenacite in Maine, Yeates : Tableaux des Mineraux des 

 Roches, etc., Michel-Le>y et Lacroix, 259.— Index der Krystallformen der 

 Mineralien, Goldschmidt: Report of the Royal Commission, etc., 260. 



Miscellaneous Scientific Intelligence. — Report of the TJ. S. Coast and Geodetic Sur- 

 vey for 1887, 260. — Aid to Astronomical Research, Bruce: Construction of 

 buildings in Earthquakes countries, Milne: A Handbook of Engine and Boiler 

 Trials, etc., Thurston : The Science of Metrology, Noel. 



