On Pure Cultures of a Uredinc, Puccinia dispersa (AV //,*.). 



February 20, 1902. 

 Sir WILLIAM HUGGINS, K.C.B., D.C.L., President, in the Chair. 



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

 ordered for them. 



The following Papers were rend : 



I. " On Pure Cultures of a Uredine, Pnrcinia (Utperxi (Eriks.)." By 

 Professor MARSHALL WARD, F.R.S. 



II. " On the Physics and Physiology of Protoplasmic Streaming in 

 Plants." By Dr. A. J. EWART. Communicated by Professor 

 GOTCH, F.R.S. 



III. " On a Pair of Ciliated Grooves in the Brain of the Ammocoete, 



apparently serving to promote the Circulation of the Fluid in 

 the Brain-cavity." By Professor A. DENDY. Communicated 

 by Professor HOWES, F.R.S. 



IV. " On the Interpretation of Photographic Records of the Response 



of Nerve obtained with the Capillary Electrometer." By 

 G. J. BURCH, F.R.S. 



V. "Note on the Anomalous Dispersion of Sodium Vapour." 'By 

 Professor W. H. JULIUS. Communicated by Professor C. V. 

 BOYS, F.R.S. 



VI. "Note on Mr. Bateson's Paper, 'Heredity, Differentiation, and 

 other Conceptions of Biology: a Consideration of Professor 

 Karl Pearson's Paper " On the Principle of Homotyposis." ' 

 By Professor KARL PEARSON, F.R.S. 



"On Pure Cultures of a Uredine, Puccinia dispersa (Eriks.)." 

 By H. MARSHALL WARD, F.R.S. Received February 5, 

 Read February 20, 1902. 



During the course of a long series of experiments, designed to seek 

 further information regarding the relations between the host and the 

 parasite, in the case of certain species of Bromm and the Rust-fungus, 

 Puccinia dispersa (Eriks.), it fell out that a simple method of obtaining 

 pure cultures of both host and parasite was attainable. 



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