VI 



CONTENTS. 



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Number 238. 



Page 

 Art. XXVI. — The Mammals and Horned Dinosaurs of the 

 Lance Formation of Niobrara County, Wyoming ; by 

 R. S. Lull 319 



XXVII. — A Note on the Qualitative Detection and Sepa- 

 ration of Platinum, Arsenic, Gold, Selenium, Tellurium 

 and Molybdenum; by P. E. Browning 349 



XXVIII. — On Aventurine Feldspar ; by O. Andersen. 



(With Plates I-III) 351 



XXIX. — Anodic Potentials of Silver : II. Their Role in the 

 Electrolytic Estimation of the Halogens ; by J. H. 

 Reedy 400 



XXX. — Nephelite Syenites of Haliburton County, Ontario ; 



by W. G. Foye 413 



XXXI.— Post-Glacial History of Boston; by H. W. Shimer 437 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Improvement of High Boiling Petroleum Oils, A. M. 

 McAfee, 443. — Arsenious Oxide as an Alkalimetric Standard, A. W. C. 

 Menzies and F. N. McCarthy : A New Method for the Qualitative Sepa- 

 ration and Detection of Arsenic, Antimony and Tin, F. L. Hahn, 444. — 

 An Alleged Allotropic Form of Lead, H. Heller : Reflection of Gas 

 Molecules, R. W. Wood, 445.— The Stark Effect for Solids, C. E. Men- 

 denhall and E. W. Wood, 447. 



Obituary — F. W. Putnam: J. H. Van Amringe: K. E. Guthe: P. Ehrlich: 

 J. von Pater, 448. 



