iv CONTENTS. 



Proceedings, etc. 



'} 



PAGE 



Notices of Books . . . . . . . . .185 



Proceedings from March 28th to June 27th, 1916, inclusive . 188 



Obituary Notices : 



B. T. Lewis, F.R.M.S 201 



Feedeeic Enock, F.L.S., F.R.M.S., F.E.S. . . .203 



PART No. 80, APPvIL 1917. 

 Papers. 



David Beyce. Notes on the Collection of Bdelloid and other 



Rotifera. (Figs. 1 and 2 in text) ..... 205 



Aethur Dendy, D.Sc, F.R.S, The President's Address. The 

 Chessman Spicule of the Genus Latrunculia ; a study in 

 the origin of specific characters, (Plates 15-17) . . 231 



G. T. Hareis. The Desmid Flora of Dartmoor. (Plates 18 and 



19) 247 



C. D. Soar, F.L.S., F.R.M.S. Two New Species of Hydracarina 

 or Watermites, Dartia Harrisi and Eylais Wilsoni (Plates 

 20 and 21) 277 



Proceedings, etc. 



Notices of Books ......... 283 



Proceedings from October 24th, 1916, to February 27th, 1917, 



inclusive ......... 287 



Fifty-first Aimual Report (191 6) 298 



Treasurer's Report ........ 305 



PART No. 81, NOVEMBER 1917. 



Papers. 

 W. M. Bale, F.R.M.S. Note on the Measurement of Magnifying 



Powers. (Fig. 1 in text) ...... 307 



Maurice A. Ainslie, R.N., B.A., F.R.A.S. The Measurement 



of Magnifying Power. A Note on Mr. Bale's Paper . 315 



C. F. Rousselet, F.R.M.S. Some further Notes on Collecting 



and Mounting Rotifera . . . . . .321 



Notes. 



Technical Optics ......... 329 



Notices of Books : 



On Growth and Form : D'ArcyW. Thompson . . . 333 



Proceedings, etc. 



Proceedings from March 27th, 1917, to June 26th, 1917, inclusive 336 



Obituary Notices : 



Robert Beaithwaite ....... 350 



Alpheus Smith (Portrait) 351 



