CONTKN T S. 



Art. 1\. — Experimental Investigation on the Reflection of 

 Light at Certain Metal-Liquid Surfaces ; by L. P. 

 Wheeler 85 



X. — Recent Gravity Work in the United States; by W. 



Bowie . 101 



XI. — Crystal Forms of Pyromorphile ; by 0. Bowles 11-1 



XII. — Some New Mechanical Quadratures ; by G. F. Becker 117, 



XIII. — Comparative Age of the Recent Crinoid Faunas ; 



by A. H. Clark '.. 127 



XIV. — Study of Some American Fossil Cycads. Part V. 



Further'Notcs on Seed Structures; by*G. R. Wieland 133 



XV. — New Locality of Pyrrhotite Crystals and their Pseu- 



domorphs ; by C. IT. Smyth, Jr. 156 



XVI. — Ferritungstite, a New Mineral ; by W. T. Scuallee 161 



XVII. — Method of Remo\ ing Tests from Fossils; by S. S. 



Buckman 163 



XVIII. — Decomposition of the Cerium Earth Double Sul- 

 phates with the Alkali Sulphates by Fusion with Char- 

 coal ; by P. E. Browning and P. L. Blumenthal 164 



SCIENTIFIC INTELLIGENCE. 



Geology and Mineralogy — La Granodiorita de Concepcion del Oro en el 

 Estado de Zacatecas, y sus Formaciones de Contacto, A. Bergeat : Four- 

 teenth Annual Eeport of the Geological Commission of the Cape of Good 

 Hope for 1909, 166.— Norwegian Geological Survey : State of Tennessee — 

 State Geological Survey: HaDdbuch der Mineralogie, C. Hintze : Cata- 

 logue of the Minerals of Tasmania, W. F. Petterd : Minerals of Guana- 

 juato, Mexico, E. Wittich, 167. — Minerals from the Belgian Congo, H. 

 Buttgenbach : Die Airwendung der stereographischen Projektion bei 

 Imstallographischen Untersuchungen, H. E. Boeke, 168. 



Miscellaneous Scientific Intelligence — Second Course in Algebra, H. E. 

 Hawkes, W. A. Luby and F. C. Totjton : Les Progr^s et L'Evolution de 

 L'Astronomie, J. Mascart, 168. 



