CONTENTS 



Art. XLT. — Two New Ceratopsia from the Laramie of 

 Converse County, Wyoming; by J. B. Hatcher. (With 

 Plates XII, XIII.)--- 413 



XLII. — Restoration of the Horned Dinosaur Diceratops ; 



by Richard S. Lull. (With Plate XIV.) 420 



XLIIL — Triassic System in New Mexico ; by Charles R. 



Keyes ... 423 



XLIY. —Structure of the Upper Cretaceous Turtles of New 



Jersey: Agomphus ; by G. R. Wikland 430 



XLV.-^-The Cambro-Ordovician Limestones of the Middle 



Portion of the Valley of Virginia; by H. D. Campbell 445 



XLVI. — Relations of Ions and Nuclei in Dust-free Air; by 



Carl Barus 448 



XLVII. — Additional Notes upon the Estimation of Cad- 

 mium by Means of the Rotating Cathode, and Summary; 

 by Charles P. Flora . _ 454 



XLVIII. — The Estimation of Cadmium as the Oxide ; by 



Charles P. Flora ._ 456 



XLIX. — The Mounted Skeleton of Triceratops prorsus in 

 the IT. S. National Museum; by C. Schuchert. (With 

 Plate XV.) ...._. 458 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Pliysics. — A New Formation of Diamond, Sir W. Crookes: 

 A New Compound of Iron, Otto Hauser : Nitrosyl Fluoride, Rufe and 

 Stauber, 460. — The Atomic Weight of Strontium, T. W. Richards : 

 Qualitative Analysis, E. H. S. Bailey and H. P. Cady : Charging Effect 

 of Rontgen Rays, Karl Hahn, 461. — Emission of Negative Corpuscles by 

 the Alkali Metals, J. J. Thomson : A New Method of afiowing the Presence 

 of Neon, Krypton, and Xenon, S. Valentiner and R. Schmidt: The 

 Mechanical Properties of Catgut Musical Strings, J. R. Benton, 462. 



Geology and Mineralogy. — Iowa Geological Survey, Volume XV, 463. — Sum- 

 mary Report of the Geological Survey Department of Canada, R. Bell: 

 Glaciation of Southwestern New Zealand, E. C. Andrews, 464. — Mastodon- 

 Res te aus dem interandinen Hochland von Bolivia, J. F. Pompeckj : 

 Description of New Rodents and Discussion of the Origin of Daemonelix, 

 O. A. Peterson, 465. — Economic Geology of the Bingham Mining District, 

 Utah, 466.— Economic Geology, 467. — Minerals in Rock Sections, L. Mel. 

 Luquer, 468. 



Miscellaneous Scientific Intelligence. — National Academy of Sciences, 468. — 

 The Geological Society of America : A Laboratory Guide in Bacteriology, 

 Paul G. Heinemann: British Tunicata, Alder and Hancock, 469. — Cata- 

 logus Mammalium tarn viventium quam fossilium, E. L. Trouessart : 

 Carnegie Institution of Washington : A Handbook of the Trees of Cali- 

 fornia, A. Eastwood, 470. 



Obituary. — Professor Dewitt Bristol Brace, Professor Ralph 'Copeland, 

 Professor D. W. von Bezold, 470. 

 Index to Vol. XX, 471. 



TEX-VOLUME INDEX. 



An extra number, containing a full Index to volumes XI to XX of the 

 Fourth Series, will be ready in December or January. Sent only to those 

 who specially order it. Price one dollar. 



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