IV 



Page 



On the Development of the Atrial Chamber of Amphioxus. By Arthur 

 "Willey, Student of University College, London 80 



On a Method of determining the Value of Eapid Variations of a Differ- 

 ence of Potential by means of the Capillary Electrometer. By George 

 J. Burch, B.A . 89 



A Bacteria-killing Globulin. By E. H. Hankin, B.A., St. John's College, 

 Cambridge, Junior George Henry Lewes Student 93 



List of Presents...., .. 101 



No. 293. June 5, 1890. 

 Election of Fellows 104 



Account of recent Pendulum Operations for determining the relative 

 Force of Gravity at the Kew and Greenwich Observatories. By 

 General Walker, C.B., F.E.S., LL.D 105 



Observations on Pure Ice. Part II. By Thos. Andrews, F.E.S., 

 M.Inst.C.E 106 



The Passive State of Iron and Steel. Part I. By Thos. Andrews, 

 F.E.SS.L. and K, M.Inst.C.E 116 



On the Superficial Viscosity of Water. By Lord Eayleigh, Sec. E.S 127 



Experiments with Lord Eayleigh's Colour Box. By Arthur Schuster, 



F.E.S 140 



List of Presents.... 149 



June 12, 1890. 



On a Ee-determmation of the principal Line in the Spectrum of the 

 Nebula in Orion, and on the Character of the Line. By William 

 Huggins, D.C.L., LL.D., F.E.S., and Mrs. Huggins 151 



Note on the Photographic Spectrum of the Great Nebula in Orion. By 

 William Huggins, D.C.L., LL.D., F.E.S., and Mrs. Huggins 151 



On a new Group of Lines in the Photographic Spectrum of Sirius. By 

 William Huggins, D.C.L., LL.D., F.E.S., and Mrs. Huggins 152 



Preliminary Note on the Development of the Tuatara (Sphenodon 

 punctatum). By Professor A. P. W. Thomas, M.A., F.L.S., F.G.S., 

 University College, Auckland, N.Z 152 



On the Position of the Vocal Cords in Quiet Eespiration of Man, and , 

 on the Eeflex-Tonus of their Abductor Muscles. By Felix Semon, 

 M.D., F.E.C.P., Assistant Physician in charge of the Throat Depart- 

 ment of St. Thomas's Hospital, and Laryngologist to the National 

 Hospital for Epilepsy and Paralysis, Queen Square 156 



A Eecord of the Eesults obtained by Electrical Excitation of the so- 

 called Motor Cortex and Internal Capsule in an Orang Outang (Simia 

 satyrus). By Charles E. Beevor, M.D., F.E.C.P., and Victor Horsley, 

 B.S., F.E.S. (From the Laboratory of the Brown Institution.) 159 



