CONTENTS. 



Number 75. 



Page 

 Art. XIV. — Ventral Integument of Trilobites ; by C. E. 



Beeciier. (With Plates II-V.) 165 



XV. — Igneous Rocks from Eastern Siberia; by H. S. 



Washington 175 



XVI.— A Cosmic Cycle, Part III ; by F. W. Vert 185 



XVII. — Studies of the Eocene Mammalia in the Marsh Col- 

 lection, Peabody Museum ; by J. L. Wortman. (With 

 Plate VI.) 197 



XVIII. — Experimental Method in the Flow of Solids and 

 its Application to the Compression of a Cube of Plastic 

 Material; by J. R. Benton 207 



XIX. — Occurrence of Monazite in Iron Ore and in Graphite ; 



by O. A. Derby _ 211 



XX — Molecular Weights of some Carbon Compounds in 

 Concentrated Solutions with Carbon Compounds as Sol- 

 vents ; by C. L. Speyers ._ 213 



Clarence King. ..„ _. 224 



SCIENTIFIC INTELLIGENCE. 



Chemistry and Physics — Manufacture of Sulphuric Acid by the Contact Pro- 

 cess, Knietsch : Metallic Carbides. Moissan, 238. — Potassium Hydride, 

 Moissan: Electrical Conductivities produced in Air by the Motion of Negative 

 Ions, Townshend : Kind of Radio-activity imparted to certain Salts by Cathode 

 Rays, J. C. McLennan, 240. — Radio-active Bodies, M. P. and S. Curie: Out- 

 lines of Electrochemistry, H. C Jones: Chemische Organisation der Zelle, F. 

 Hofmeistee, 241. — Beitraege zur Chemischen Physiologie und Pathologie, F„ 



HOFMEISTER, 24 2. 



Geology and Natural History — Occurrence of Chrompicotite in Canada, G. 

 Chr. Hoffmann, 242. — Still Rivers of Western Connecticut, W. H. Hobbs : 

 Petrographisches Praktikum. R. Rheinisch, 243. — Grasses of Iowa, L. H. 

 Pammel, J. B. Weems, and F. Lamson-Scribner: Birds of North and Middle 

 America, R. Ridgeway, 244. 



Miscellaneous Scientific Intelligence — Smithsonian Institution, Documents Rela- 

 tive to its Origin and History, 1835-1899: Scientia, 244. 



