CONTENTS. 



Sixty Years of Chemical Progress. 



By E. S. Grcic. M.A. 463 

 International Union for Cooperation in Solar 

 Research. 



Br W. ShacklctoiK F.R.A.S., A.R.C.S. 465 

 Opinions Rendered hv the International Commis- 

 sion ON /Zoological Nomenclature. July, 1910. 

 By the Rci: Thomas R. R. Stehhing. M.A.. F.R.S. 46S 



The Spectroheliograph. By FraiiK- C. Dennett 470 



Treasures of the Snow. By Jean M. Tlioinpson 472 



The Face of the Sky for December. 



By \V. Shackleton. F.R.A.S.. A.R.C.S. 474 

 Solar Disturbances During October. 1910. 



By Frank C. Dennett 475 



Correspondence ... ... ... 476 



Queries and Answers 477 



A Zoological Gathering ... ... ... ... 478 



Notes. — 



.\stronomy. By G. F. Chambers. F.R..A.S. 479 



Botany. By Professor F. Cavers. D.Sc.. F.L.S. 4S0 



Notes icontinuedK — 

 Chemistry. 



By C. Ainsworth Mitchell. B.A. (0.\-on), F.I.C. 482 

 Economic Bioloif\-. 



By Walter E. CoUin^e. M.Sc.. F.L.S. . F.E.S. 4S2 

 Geolog}-. 



By Russell F. GicinnelL B.Sc. A.R.C.S.. F.G.S. 483 

 Meteorologv. By John A. Curtis, F.R.Met.Soc. 484 

 Microscopy. ' By A. W. Slieppard. F.R.M.S. 485 



Photography. 



By C. E. Kenneth Mees. D.Se. \Lond.), F.C.S. 487 

 Physics. By \V . D. Eggar. M.A. 488 



Seismology. By Charles Davison, Sc.D.. F.G.S. 489 

 Zoologj'. By Professor J . Artliur Thomson, M.A. 489 



Reviews ... ... ... 490 



X-Rays. By Reginald .Morton. M.D. 494 



The Selborne Society and Plant Protection... 499 

 The Measurement of Perseveration and its 

 Value as an Index of Mental Character. 



By John Gray. 500 

 Thorvald Nicolai Thiele. 



Bv F. A. Bellamy, Hon. M.A.. F.R.A.S. 504 



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