(^ Index XI-XX, now ready. Price $1.00. 



CONTENTS. 



Page 



Art. XL — An Investigation into the Elastic Constants of 



Rocks; by F. D. Adams and E. G. Coker 95 



XII. — Dakotan Series of Northern New Mexico ; by C. R. 



Keyes 124 



XIII. — Plauenal Monzonose (Syenite) of the Plauenscher 



Grund ; by H. S. Washington . 129 



XIV. — Colloidal Nuclei and Ions in Dust-free Air saturated 



with Alcohol Vapor; by C. Barus 136 



XV. — Russian Carboniferous and Permian compared "with 



those of India and America ; by C. Schuchert . _ 143 



XVI. — Notes on Some Eruptive Rocks in Mexico ; by F. N. 



Guild .__ = 159 



XVII. : — Hydrolysis of Salts of Iron, Chromium, Tin, Cobalt, 



Nickel, and Zinc in the Presence of Iodides and Iodates; 



by S. E. Moody ; _ _ . 1T6 



SCIENTIFIC INTELLIGENCE. 



Geology and Natural History — Geodetic Evidence of Isostacy, J. F. Hat- 

 ford, 185. — Pleistocene Deposits of South Carolina, G. T. Pugh, 186. — 

 Geography and Geology of Alaska, A. H. Brooks, C. Abbe, Jr. and E. U. 

 Goode : Geology and Mineral Eesources of part of the Cumberland Gap 

 Coal Field, Kentucky, G. H. Ashley and L. C. Glenn : Pleistocene 

 Deposits of Sankoty head, Nantucket, and their Fossils, J. A. Cushman, 

 187. — Tertiary and Quaternary Pectens of California, E. Arnold : Cam- 

 brian Faunas of China, C. D. Walcott : Plant Eesponse as a Means of 

 Physiological Investigation, J. C. Bose, 188. — Heather in Townsend, 

 Mass. : Biology of the Frog, S. J. Holmes : A Course in Vertebrate Zoology, 

 H. S. Pratt, 190. — Life of Animals, E. Ingersoll, 191. 



Miscellaneous Scientific Intelligence — Eecent Text-books on Astronomy, 191. 

 — Publications of the Eoyal Society of London, 192. — Physical Optics, E 

 W. Wood, 193. 



Obituary — H. A. Ward : C. E. von der Osten Sacken : L. Brackebush, 

 194. 



