CONTENTS TO Trr >LUME XXVI. 



Number 151. 



Page 

 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 



J II. — 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 Elateridae from Florissant ; by H. F. 



Wickiiam .- 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 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, Eubidium, 

 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. 



