206 transactiojss, natural history society of glasuov?. 



26th April, 1904. 



Mr. Peter Ewing, F.L.S., President, in the chair. 



On behalf of the Rev. A. S. Wilson, M.A., B.Sc, Mr. John 

 Renwick read a report on an excursion to Rosyth (p. 190). 



Mr. Alex. Ross exhibited specimens of Geranomyia tonicolor, 

 Hal., and explained that this fly owes its position as a Scottish 

 recoi'd to a single specimen taken at Holy Loch in 1897 by Mr. 

 Robert Henderson. Mr. Ross found this tipulid to be very com- 

 mon at the Isle of Whithorn, Wigtownshire, in the summer of 

 1902. 



The President (Mr. Ewing) exhibited Sarracenia purpurea, 

 Linn., and described its anatomy and physiology. 



Mr. R. S. Wishart, M.A., exhibited plants from Jersey. 



Mr. R. Garry, B.Sc., gave details of methods for preparing 

 microscopic slides of Spirogyra and other fresh-water Algae, and 

 illustrated his remarks by an exhibition of specimens. His 

 methods were as follows : — -Fresh material is fixed in a solution 

 of Chromic Acid in water containing about "5 7„ Chromic Acid, 

 a few drops of Acetic Acid being added. After removal from 

 the solution the material is washed in several changes of water, 

 then stained and slowly dehydrated as follows : — The stained 

 material is placed at the bottom of a narrow test tube, alcohol is 

 carefully poured on the surface of the water, slow diffusion takes 

 place, and in the course of twenty-four hours the material may be 

 removed from the tube and treated with absolute alcohol without 

 fear of distortion. The material is then cleared in oil of cloves, 

 precautions being used to prevent ^dolent diffusion currents. A 

 small quantity of the clearing medium may then be placed in a 

 test-tube, a little absolute alcohol poured on the surface of the 

 cloves, and the material placed in alcohol. In a few hours the 

 material will be found in the oU of cloves at the bottom of the 

 tube in a suitable condition for mounting in balsam — a weak 

 solution of balsam in xylol being used. Slides prepared in this 

 way may be considered as permanent, and although the green 

 colour is lost, suitable staining re-agents wUl demonstrate the 

 various protoplasmic structures, such as nucleus, chloroplastid, 

 pyrenoids, &c. 



