CONTENTS. 

 VOL. XLIX. 



No. 296. December 11, 1890. 



Pae 



On Ellipsoidal Harmonics. By W. D. Niveu, F.RS 1 



Photometric Observations of the Sun and Sky. By William Brennand.... 4 



Determinations of the Heat Capacity and Heat of Fusion of some Sub- 

 stances to test the Validity ef Person's Absolute Zero. By Spencer 

 Umfreville Pickering, M.A., F.RS 11 



On Wolf and Rayet's Bright-Line Stars in Cygnus. By William Hug- 

 gins, D.C.L., LL.D,, F.RS., and Mrs. Huggins 33 



On Stokes's Current Function. By E. A. Sampson, Fellow of St. John's 

 College, Cambridge 46 



List of Presents 53 



December 18, 1890. 



On a Determination of tke Boiling Point of Sulphur, and on a Method of 

 Standardising Platinum Resistance Thermometers by reference to it. 

 By Hugh L. Callendar, M.A., Fellow of Trinity College, Cambridge, 

 and E. H. Griffiths, M.A., of Sidney Sussex College, Cambridge 56 



On the Generic Identity of Sceparnodon and Pkascolonus. By E. Lydekker, 

 B.A. (Plate 1) .". 60 



Contribution to the Study of the Vertebrate Liver. By Sheridan D616- 

 pine, M.B., Edin 64 



On certain Conditions that modify the Virulence of the Bacillus of 

 Tubercle. By Arthur Eansome, M.D., F.E.S 66 



List of Presents 73 



No. 297. January 8, 1891. 



On the Minute Structure of the Muscle-Columns or Sarcostyles which 

 form the Wing Muscles of Insects. Preliminary Note. By E. A. 

 Schafer, F.RS, \ 76 



On the Minute Structure of Striped Muscle, with Special Reference to a 

 New Method of Investigation by means of " Impressions" stamped in 

 Collodion. By John Berry Haycraft, M.D., D.Sc., F.E.S.E 76 



On the Eeflection and Refraction of Light at the Surface of a Magnetised 

 Medium. By A. B. Basset, M.A., F.RS * 76 



Further Contributions to the Metallurgy of Bismuth. By Edward 

 Matthey, F.S.A., F.C.S., Assoc. Eoy. Sch. Mines 78 



List of Presents.... , 80 



