190 PROCEEDINGS OF THE 



At the 54:7tli Ordinary Meeting of the Club, held on Decem- 

 ber 9th, the President, Dr. A. B. Rendle, M.A., F.R.S., in the chair, 

 the minutes of the meeting held on November 11th were read and 

 confirmed. 



Messrs. Arthur E. McClure, Leslie Price, F. W. Ellis, Harry 

 Walkinson, Harry Wheeler, F.G.S., and John H. A. Verinder 

 were balloted for and duly elected members of the Club. Five 

 nominations were read for the first time. 



The Secretary made the following announcement : The 

 Committee have decided that no meeting shall be held on Decem- 

 ber 2Srd, as it is so near Christmas. The next meeting of the 

 Club will be held on January 13th, 1920. At this meeting Sir 

 Nicolas Yermolofi, K.C.B., F.L.S., F.R.M.S., will read a paper 

 entitled " Notes on Continuity and Discontinuity in Nature, as 

 Illustrated by Diatom Structure," and Mr. C. D. Soar will read an 

 abstract of a paper on " Water Mites of the Genus Eylais, written 

 in conjunction with W. Williamson, F.R.S.E., F.L.S. The 

 Committee hope that new members will avail themselves of the 

 opportunities afforded by the Conversational Meetings to bring up 

 their microscopes and seek advice or assistance in any difficulties 

 connected with either their instruments or specimens. There are 

 many members who are experts in various branches of natural 

 history, and others who are skilled in microscopical manipulation 

 and technique, and it is always a pleasure to any of these to be of 

 assistance to those less-experienced members who are anxious 

 to overcome the many difficulties that beset the beginner. 



The Secretary read a note from Mr. E. M. Nelson on " Capped 

 Eyepieces." Mr. Nelson gave detailed results of an investigation 

 of the effect on the visible image of eyepiece-caps. He found that 

 caps were a decided advantage. In addition to their keeping the 

 eye-lens clean by preventing it from being touched, they improved 

 the image, Mr. Nelson found that in most cases the size of the 

 hole in the cap which gave the best results was smaller than that 

 commonly used, but in no case was it anything like so small as 

 the Ramsden disc. Stereoscopic effect with a binocular was also 

 improved by reducing the size of the hole. Mr. N. E. Brown 

 confirmed Mr. Nelson's results. Mr. Maxwell referred members 

 to the Journal for information concerning the effect of a very 

 small hole moved about in the plane of the Ramsden disc. Mr. 

 Maurice Blood said that the only conceivable effect of Mr. Nelson's 



