CONTENTS 



Page 



Art. I. — Relations of Subjacent Igneous Invasion to Regional 



Metamorphism; by J. Barrell 1 



Art. II. — Note on Augite from Vesuvius and Etna; by H. 



S. Washington and H. E. Merwin 20 



Art. III. — Chionopbila Benth., a Morpbological Study; by 

 Theo. Holm. (Witb 15 figures drawn from nature by 

 the autbor) ". 31 



Art. IV. — Geology of tbe Muddy Mountains, Nevada, witb 

 a Section to tbe Grand Wasli Cliffs in Western Arizona: 

 by C. R. LoNGWELL 39 



Art. V. — Tbe Stanley Sbale of Oklaboma; by C. W. Honess 63 



Art. VI. — Poj>ocatepetl again in Activity; by P. Waitz. . . 81 !^ 



SCIEN^TIFIC INTELLIGENCE. 



Chemistry and Fhysica — A Revision of the Atomic Weight of Aluminium, 

 T. W. EiCHARDS and H. Krepelka : The Chemists' Year Book, 1920, 

 F. W. Atack, 88. — Dictionary of Explosives, A. Mahshat^l: Catalysis 

 and its Industrial Applications, E. JoBijiNCi : Aruerican Lubricants, L. B. 

 LocKHART ; Fuel Oil in Industry, S. O. Andros -. Spectra of Isotopes, 

 T. R. Merton, 89. — Magnetic Susceptibilities of Low Order, 90. — The 

 Airplane. F. Bedell: A Field and Laboratory Guide in pv.^-wirui Nature 

 Study, E. R. Downing, 91.— Annuaire pour I'An 1920, 92. 



Geology — Der Siidrand der Puna de Atacama (NW-Argentinitn) ; Eiu Beitiag 

 zur Kenntniss des Andinen Gebirgstypus und zu der Frage dev Gebiigs- 

 bildung. W. Penck. 92.— Der Selpausselka, L. Leivibk.\: De marine 

 Kridtaflejringer, J. P. J. Ravn, 9;J.— Illinois State »l!eological Survey, F. 

 W. DeWolf : Bulletins of the Buffalo Society of Natural Sciences. 94. — 

 Guide to the Mineral Collections in the Illinois State Musenm, A. R. 

 Crook, 95. 



Miscellaneous Scientific Intelligence —Report of the Secretary of the Smithson- 

 ian Institution. C. D. Walcott. for the year ending June 80, 1920, 95. — 

 Publications of the Allegheny Observatory of the University of Pittsburgh, 



F. SCHLESIKGER, 9H. 



Obituary— M. Maroules : K. H. Struve : Y. Delage, 96. 



:S^ A TEN VOLUME INDEX 



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