249 



PROCEEDINGS OF THE SOCIETY. 



MEETING 



Held on the 21st of February, 1906, at 20 Hanover Square, W. 

 Dr. D. H. Scott, F.R.S., etc., President, in the Chair. 



The Minutes of the Annual Meeting of the 17th of January, 190(5, 

 were read and confirmed, and were signed by the President. 



The List of Donations to the Society (exclusive of exchanges and 

 reprints) received since the last Meeting, was read, and the thanks of the 

 Society voted to the donors. 



From 

 Herdman, W. A. Report to the Government of Ceylon on I 



the Pearl Oyster Fisheries of the Gnlf of Manaar. Parts > The Royal Society. 

 in. and IV. (4to, London, 1905) ) 



(The Director of the 

 Thomas S. Clarkson 

 School of Techtwlogy 

 Warming, Dr. Eug. (Hon. P.R.M.S.) Dansk Plantevgekst.\ ™ . ri 

 (8vo, Copenhagen and Christiania, 1906) . . . / ine Autmr - 



Mr. Griffiths gave a short account of the method which he had 

 successfully adopted for mounting delicate vegetable tissues in xylo- 

 balsam so as to prevent osmotic action. The specimens were first 

 dehydrated by steeping successively in various strengths of alcohol and 

 subsequently in mixtures of xylol and alcohol. Specimens which were 

 specially delicate were previously fixed with picric acid and after washing 

 a sufficient quantity of this would remain to slightly stain portions. 

 In illustration of the subject an excellent sample of Spirogyra in con- 

 jugation was exhibited under the Microscope. The precise point at 

 which the staining should be done is determined by the alcoholic 

 strength of the stain. 



The President, in moving a vote of thanks to Mr. Griffiths, said he 

 had seen the specimens before the meeting, and was glad to find that the 

 difficulty usually experienced in mounting these delicate objects had 

 been so successfully overcome. 



Mr. Beck exhibited and described a new pattern optical bench, 

 for illumination with either ordinary or monochromatic light, the 

 various parts of which, together with the methods of using them, were 

 explained in detail. 



Dr. Hebb exhibited an objective intended to be used either as a wet 

 or dry lens, which was designed by Mr. Wenham in 1870, and made by 



