CONTENTS. 



Number 231. 



Page 



Art. XV.— The Sal ton Sea; by D. T. MacDougal 231 



XVI. — Illustrations of the Stem Structure of Tietea Singu- 



laris ; by O. A. Derby _ . 251 



XVII. — Petrographic Evidence on the Origin of the Cata- 

 houla Sandstone of Texas ; by M. I. Goldman 261 



XVIII. — Age of the Igneous Rocks of the Adirondack 



Region'; by H. P. Cushing 288 



XIX. — Unstable Chromium Sesquioxide, and Corrections of 

 Previous Work on the Heat Effect of Chromium and 

 Aluminum Sesquioxides in Fusions with Sodium Per- 

 oxide; by W. G. Mixter 295 



XX.— Note on the Shape of Pebbles; by H. E. Gregory _. 300 



XXI. — Relation of the Late Tertiary Faunas of the York- 

 town and Duplin Formations; by Julta A. Gardner... 305 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Determination of Cuprous and Cupric Sulphides in 

 Mixtures of the Two, E. Posnjak : Feldspar as a Possible Source of 

 Potash, A. S. Cushman and G. W. Coggeshall, 311. — Qualitative Test 

 for Water, E. E. Weaver: The Rare Earths, S. I. Levy, 312.— Ampere 

 Molecular Currents, H. K. Onnes, 313. — Elements of Electricity and Mag- 

 netism, W. S. Franklin and B. Macnutt: Molecular Physics, J. A. 

 Crowther, 314. — General Physics; Electricity, Electromagnetic Waves 

 and Sound, J. A. Culler, 315. 



Geology — Thirty-fifth Annual Report of the Director of the U. S. Geological 

 Survey, G. 0. Smith : Publications of the United States Geological Sur- 

 vey, 31(3. — Sixth Biennial Report of the Commissioners of the State Geo- 

 logical and Natural History Survey of Connecticut for 1913-14 : Topo- 

 graphic and Geologic Survey of Pennsylvania, R. R. Hice : The Problem 

 of Volcanism, J. P. Iddings, 318. — Pleistocene Mammals of Iowa, O. P. 

 Hay, 320. — Notes on Agelacrinidas and Lepadocystinse, with descriptions 

 of Thresherodiscus and Broekocystis, A. F. Foerste : Introduction to the 

 Study of Fossils (Plants and Animals), H. W. Shimer: Paleontology of 

 Preston County; Fossil fauna of the Conemaugh rocks, W. A. Price, 322. 

 A Beatricea-like organism from the Middle Ordovician, P. E. Raymond: 

 Middle Triassic marine invertebrate faunas of North America, J. P. Smith: 

 New Miocene Coleoptera from Florissant, H. F. Wickham, 323. 



Miscellaneous Scientific Intelligence — Insects Injurious to the Household, 

 G. W. Herrick. 323.— Germ -cell Cycle in Animals, R. W. Hegner : 

 Dynamic Evolution ; A Study of the Causes of Evolution and Degeneracy, 

 C. L. Redfield: Physikalische Chemie der Zelle und der Gewebe, R. 

 Hober, 324 — Infection and Resistance, H. Zinsser: British Museum Pub- 

 lications, 325. 



Obituary— A. W. Phillips : C. F. Brackett : B. Sharp : Sir G. Nares: 

 J. S. Harding: F. W. Rudler, 326. 



