CONTENTS. 



Art. I. — Emission of Electricity from the Induced Activity 



of Radium ; by W. Duane 1 



II. — Ilvaite from Shasta County, Cal. ; by B. Prescott 14 



III. — Mechanics of Igneous Intrusion (Third Paper) ; by 



R. A. Daly.. 17 



IV. — Rhinocerotidse of the Lower Miocene ; by F. B. Loomis 51 



V. — Description of Tertiary Plants ; by T. D. A. Cock- 



erell 65 



VI. — Descriptions of Tertiary Insects ; by T. D. A. Cock- 



erell 69 



VII — New Fossil Elateridse from Florissant ; by H. F. 



Wickham 76 



VIII. — Estimation of Iron and Vanadium in the Presence of 



One Another ; by G. Edgar _ _ . „ 79 



IX. — Estimation of Cerium in the Presence of the other Rare 

 Earths by the action of Potassium Ferricyanide ; by 

 P. E. Browning and H. E. Palmer I _ 83 



X. — Estimation of Chromium as Silver Chromate ; by F. A. 



Gooch and L. H. Weed 85 



XI. — Standardization of the Fog Chamber by the aid of 



Thomson's Electron ; by C. Barus 87 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Volumetric Method for Chlorates, Knecht : Atomic 

 Weight of Radium, Thorpe, 91. — Polyiodides of Potassium, Rubidium, 

 and Caesium, Foote and Chalker : Volumetric Method for Copper, 

 Jamieson : Thermodynamics of Technical Gas-Reactions, F. Haber, 92. — 

 Search for Fluctuations in the Sun's Thermal Radiation through their 

 Influence on Terrestrial Temperature, S. Newcomb, 93. 



Geology — Early Devonic History of New York and Eastern North America, 

 J. M. Clarke, 93. — Publications of the United States Geological Survey, 

 95. — Maryland Geological Survey : Iowa Geological Survey, 97.— Wis- 

 consin Geological and Natural History Survey : Geological Map of Cape 

 of Good Hope, A. W. Rogers and A. L. du Toit : Variations Periodiques 

 des Glaciers, Xllme Rapport, 1906, Ed. Bruckner et E. Muret : Cera- 

 topsia, J. B. Hatcher, 98. 



Miscellaneous Scientific Intelligence— Harvard College Observatory : Publica- 

 tions of the Allegheny Observatory of the Western University of Penn- 

 sylvania : Carnegie Institution of Washington, 99. — Maryland Weather 

 Service : Apodous Holothurians, H. L. Clark : American Association for 

 the Advancement of Science : International Catalogue of Periodicals, 100. 



Obituary — M. Albert Lapparent : Karl A. Mobius : M. Pierre J. A. 

 Bechamp : Robert Chalmers : William A. Anthony. 



