IV CONTENTS. 



]Sram"ber 80. 



Page 

 Art. XIII. — Terraces of the Westfield River, Mass. ; by W. 



M. Davis. (With Plate IV) _ 77 



XIV. — Cretaceous Turtles, Toxochelys and Archelon, with a 

 Classification of the Marine Testudinata ; by G. K. 

 WiELAND _ _ 95 



XV. — Magnetic Effect of Electric Displacement ; by J. B. 



Whitehead, Jr 109 



XVI. — Certain Relations of Plant Growth to Ionization of 



the Soil ; by A. B. Plowma]S^__ 129 



XVII. — Demagnetizing Effects of Electromagnetically Com- 

 pensated Alternating Currents ; by Z. E. Ceook 133 



XVIII. — Nepheline-Syenites and other Syenites near Port 



Coldwell, Ontario ; by A. P. Coleman 147 



XIX. — Double Ammonium Phosphates in Analysis ; by M. 



Austin _ _ 156 



XX. — Electrical Resistance of Glass, Quartz, Mica, Ebonite 



and Gutta-percha ; by O. N. R(»od 161 



SCIENTIFIC INTELLIGENCE. 



Miscellaneous Scientific Intelligence — American Association, 166. 

 Obituary — Dr. Carlo Riva, 166. 



