Vll 



IV. " On the Laws governing Electric Discharges in Gases at Low 

 Pressures." By W. R. Carr. Communicated by Professor 

 J. J. Thomson, F.R.S. 



V. " The Differential Invariants of a Surface, and their Geometric 

 Significance." By Professor A. R. Forsyth, F.R.S. 



March 12, 1903. 



Sir WILLIAM HUGGINS, K.C.B., O.M., President, followed by 

 Professor J. W. JUDD, C.B., Vice-President, in the Chair. 



A List of the Presents was laid on the table, and thanks ordered for 

 them. 



The following papers were read : — 



I. " On the Histology of Uredo dispersa, Erikss., and the ' My co- 

 plasm ' Hypothesis." By Professor Marshall Ward, F.R.S. 



II. " The Statolith-theory of Geotropism." By F. Darwin, F.R.S. 



III. " A Study of a Unicellular Green Alga, occurring in Polluted 



Water, with especial reference to its Nitrogenous Meta- 

 bolism." By Miss H. Chick. Communicated by Professor 

 R. Boyce, F.R.S. 



IV. " A Comparative Study of the Grey and White Matter of the 



Motor-cell Groups and of the Spinal Accessory Nerve in the 

 Spinal Cord of the Porpoise (Phocce.na communis)." By Dr. D. 

 Hepburn and Dr. D. Waterston. Communicated by Sir 

 William Turner, F.R.S. 



V. " The (Estrous Cycle and the Formation of the Corpus Luteum 



in the Sheep." By F. H. A. Marshall. Communicated by 

 Professor J. C. Ewart, F.R.S. 



VI. " On the Culture of the Nitroso-bacterium." By H. S. Fremlin. 

 Communicated by Sir Michael Foster, Sec. R.S. 



VII. " Upon the Immunising Effects of the Intracellular Contents of 

 the Typhoid Bacillus as obtained by the Disintegration of 

 the Organism at the Temperature of Liquid Air." By Dr. 

 A. Macfadyen. Communicated by Lord Lister, O.M., 

 F.R.S. 



