VI CONTENTS. 



Number 142. 



Page 



Art. XXIX. — Corpuscular Rays produced in different 



Metals by Rontgen Rays ; by C. D. Cooksey 285 



XXX. — New Species or Sub-species of Hercules Beetles from 

 Dominica Island, B. W. L, with notes on the habits and 

 larvae of the common species and other beetles ; by A. 

 H. Verrill , ._ 305 



XXXI. — Successive Cycles of Coronas ; by C. Barus 309 



XXXII. — Behavior of Molybdic Acid in the Zinc Reductor ; 



by D. L. Randall . 313 



XXXIII. — Measurement of the Optic Axial Angle of Min- 

 erals in the Thin Section ; by F. E. Wright. (With 

 Plates I and II) 317 



XXXIV. — Note on a New Radio- Active Element ; by B. B. 



Boltwood 370 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Action of Ozone upon Metallic Silver and Mercury, 

 Manchot and Kampschulte : Separation of Tellurium from the Heavy- 

 Metals, Brauner and Kuzma, 373. — Eays from Thorium Products, Hahn : 

 Decomposition of Gaseous Hydrocarbons by Ignition with Powdered 

 Aluminium, Kusnetzow, 374. — Studies on the Mode of Growth of Mate- 

 rial Aggregates ; II (Addendum) Distribution of Variations, A. J. Lotka, 

 375. — Method for the Observation of Coronas, C. Barus, 376. 



Geology — "United States Geological Survey, 376. — Carnivora from the Ter- 

 tiary Formations of the John Day Region, J. C. Merriam, 377. — Lower 

 Miocene Fauna from South Dakota, W. D. Matthew, 379. — Points of the 

 Skeleton of the Arab Horse, H. F. Osborn, 380. — Eiszeit und Urgeschichte 

 der Menschen, H. Pohlig : Physikalische Kristallographie vom Stand- 

 punkt der Strukturtheorie, E. Somerfeldt, 381. 



Miscellaneous Scientific Intelligence — Carnegie Institution of Washington : 

 Laboratory Manual of Invertebrate Zoology, G. A. Drew, 382. 



Obituary — Dr. W. 0. Atwater, 382. 



