CONTENTS. 



Number 117. 



Page 

 Art. XX. — Development of Fenestella ; by E. R. Ctjmings. 



(With Plates V, VI, and VII) 169 



XXI. — Age of the Monument Creek Formation ; by N. H. 



Darton 178 



XXII. — Iodometric Determination of Aluminium in Alumin- 

 ium Chloride and Aluminium Sulphate ;. by S. E. Moody 181 



XXIII. — Secondary Origin of Certain Granites ; by R. A. 



Daly 185 



XXIV. — Tychite, a New Mineral from Borax Lake, Califor- 

 nia, and on its Artificial Production and its Relations 

 to Northupite ; by S. L. Penfield and G. S. Jamieson 217 



XXV. — Modification of Victor Meyer's Apparatus for the 

 Determination of Vapor-Densities; by B. J. Har- 

 rington 225 



XXVI. — New Lower Tertiary Fauna from Chappaquiddick 

 Island, Martha's Vineyard ; by T. C. Brown. (With 

 Plate VIII) _ 229 



XXVII. — Production of Radium from Uranium ; by B. B. 



Boltwood . _ 239 



SCIENTIFIC INTELLIGENCE. 



Geology — Explorations in Turkestan with an account of The Basin of Eastern 

 Persia and Sistan. Expedition of 1903, under the direction of Eaphael 

 Pumpelly, 245. 



