Page 



On some further Evidence bearing on the Excavation of the Valley of the 

 Somme by River-action^ as exhibited in a Section at Drucat near Abbe- 

 ville. By Joseph Prestwich, F.R.S 135 



A Contribution to the Minute Anatomy of the Retina of Amphibia and 

 ReptUes. By J. W. Hulke, F.R.C.S., Assistant-Surgeon to the Middlesex 

 and the Royal London Ophthalmic Hospitals 138 



Notes of Researches on the Acids of the Lactic Series. — No. I. Action 

 of Zinc upon a mixture of the Iodide and Oxalate of Methyl. By 

 E. Frankland, F.R.S., Professor of Chemistry, Royal Institution, and 

 B. F. Duppa 140 



On the Joint Systems of Ireland and Cornwall, and their Mechanical Origin. 

 By the Rev. Samuel Haughton, M.D., F.R.S., Fellow of Trinity College, 

 Dublin 142 



On the supposed Identity of Biliverdin with Chlorophyll, with remarks on 

 the Constitution of Chlorophyll. By G. G. Stokes, M.A., Sec. R.S 144 



Continuation of an Examination of Ruhia munjista, the East-Indian Madder, 

 or Munjeet of Commerce. By John Stenhouse, LL.D., F.R.S 145 



On the Spectra of Ignited Gases and Vapours, with especial regard to the 

 different Spectra of the same elementary gaseous substance. By Dr. 

 Julius Pliicker, of Bonn, For. Mem. R.S., and Dr. J. W. Hittorf, of 

 Miinster 153 



On the Influence of Physical and Chemical Agents upon Blood ; * with special 

 reference to the mutual action of the Blood and the Respiratory Gases. 

 By George Harley, M.D., Professor of Medical Jurisprudence in Univer- 

 sity College, London 157 



Researches on Radiant Heat. — Fifth Memoir. Conti'ibutions to Molecular 

 Physics. By J. TyndaH, F.R.S 160 



Remarks on Sun Spots. By Balfour Stewart, M.A., F.R.S., Superintendent 

 of the Kew Observatory 168 



Description of an Improved Mercurial Barometer. By James Hicks 169 



On Mauve or Aniline -purple. By W. H. Perkin, F.C.S 170 



On the Functions of the Cerebellum. By William Howship Dickinson, 

 M.D. Cantab 177 



An Inquiry into Newton's Rule for the Discovery of Imaginary Roots. By 

 J. J. Sylvester, F.R.S 179 



Description of a Train of Eleven Sulphide-of-Carbon Prisms arranged for 

 Spectrum Analysis. By J. P. Gassiot, F.R.S 183 



The Croonian Lecture. — On the Normal Motions of the Human Eye in rela- 

 tion to Binocular Vision. By Professor Hermann Helmholtz, For. Mem. 

 R.S 186 



On the Orders and Genera of Quadratic Forms containing more than three 

 Indeterminates. By H. T. Stephen Smith, M.A., F.R.S 199 



On some Phenomena exhibited by Gun-cotton and Gunpowder under special 

 conditions of Exposure to Heat. By F. A. Abel, F.R.S 204 



On Magnesium. By Dr. T. L. Phipson, F.C.S. 



217 



