1 906-1907.] Exhibits in Natural History. 423 



EXHIBITS IN NATURAL HISTORY. 



Books of Drawings ; by Mr Charles W. Cowan. Concretion- 

 ary Nodules, with shell as nuclei, from Muscat, on the Gulf 

 of Omar ; by Dr T. B. Sprague. Peziza aurantia ; by Miss 

 Beatrice Sprague. Lantern slides of littoral and other vege- 

 tation in Ireland ; by Mr D. S. Fish. Thyas venusta, C. L. 

 Koch, a living Hydrachnid found in a pool near Midcalder ; 



stinging gnat {Culex ?) ; and a miscellaneous collection of 



lantern slides ; by Mr Williamson. Two fine specimens of the 

 Bearded Tit (Panurus hiarmicics) ; by Mr Gr. M. Brotherston. 

 Kafir Piano ; by Mr H. J. Harrison. Martin (Mustela martes) 

 and Polecat (Mustela putorius) ; by Mr Charles Campbell. 

 Living Mygale Spider from West Indies ; cast skin of same, 

 and several microscopic preparations from the skin of same 

 spider; by Mr James Adams. 



ADDRESS BY THE PRESIDENT, 



Mr JAMES EUSSELL, 

 October 23, 1907. 



On the first occasion I had the honour of addressing you from 

 this chair, I sketched out a plan of study for your consider- 

 ation ; on the second occasion, I described at some length the 

 development of the instrument which is needful for the scientific 

 prosecution of that study; and to-night I propose to bring under 

 your notice the practical results of a small part of that study, 

 by means of photo-micrographs shown upon the screen by the 

 projection - lantern. Before, however, these lantern trans- 

 parencies are exhibited, I wish to fulfil a half-promise I made 

 at the end of my last address, to give a few practical hints on 

 working with the microscope, and on the illumination of objects 

 under examination. From the time at my disposal the 

 remarks must necessarily be short, and in making them I shall 

 confine myself to my own experience. 



