CONTENTS. 



PAGE 



Edward M. Nelson, F.R.M.S. On Methods of Illumination (fig. in 



text) 289 



E. Penard, Dr. ES Sc. On some Rliizopods from Sierra Leone . . 299 



Notes. 



N. E. Brown. Some Notes on Seeds as Microscopic Objects . 307 

 T. A. O'DONOHOE, I.S.O. Dimorphism in the Spermatozoa of the 



Flea and Blow-fly 313 



Edward M. Nelson, F.K.M.S. An Improved Compound Microscope 



by James Mann (fig. in text) 317 



Notices op Books 321 



Eecent Additions to the Library 326 



Proceedings. 



Proceedings from March 28th to June 27th, inclusive .... 327 

 List of Members i xxxii 



PAET No. 70, APRIL 1912. 



Papers. 



E. A. MiNCHiN, M.A., F.R.S. President's Address Speculations 

 with regard to the Simplest Forms of Life and their Origin 

 on the Earth ' 339 



David Beyoe. On Three New Species of Callidina (Plate 12) . . 365 



Charles F. Rousselet, F.R.M.S. On Notholca triarthroides Skori- 

 kow, Catliypna hrachydactyla Stenroos, and on a new Brachi- 

 onus from Devil's Lake, North Dakota (Plate 13) . . . 371 



Henry Sidebottom. Lagenae of the South-West Pacific Ocean 



(Plates 14-21) 375 



Notes. 



James Burton. Notes on Algae collected in 1911 .... 435 



E. M. Nelson, F.R.M.S. Notes on Exhibits (Plate 22, figs. 1 and 2) . 441 

 A. A. C. Eliot Merlin, F.R.M.S. Notes on a Photograph of the 



Secondary Structure of Navicula Smitliii (Plate 22, figs. 3 and 4) 443 



Notices of Books 445 



Recent Additions to the Library 449 



Proceedings, etc. 



Proceedings from October 24th, 1911, to February 27th, 1912, inclusive 451 



Forty-sixth Annual Report 468 



Report of the Treasurer, 1911 474 



