2^ 



New Series, No. 172 (Vol. 43, Part 4). 



SEPTEMBER, 1900. 

 THE 



Price 10s. 



QUARTERLY JOURNAL 



OF 



MICROSCOPICAL SCIENCE. 



EDITEIJ BY 



E. RAY LANKESTEK, M.A., LL.D., F.R.S., 



HONORARY FELLOW OF EXETER COLLEGE, OXFORD ; CORRESPONDENT OK THE INSTITUTE OF FRANCE, 



AND OF THE IMPERIAL ACADEMY OF SCIENCES OP ST- PETERSBURG, AND OF THE ACADEMY 



OF SCIENCES OF PHILADELPHIA; FOREIGN MEMBER OF THE ROYAL BOHEMIAN 



SOCIETY OF SCIENCES, AND OF THE ACADEMY OF THE LINCEI OF ROME'; 



ASSOCIATE OF THE ROYAL ACADEMY OF BELGIUM ; HONORARY MEMBER 



OF THE NEW YORK ACADEMY OF SCIENCES, AND OF THE 



CAMBRIDGE PHILOSOPHICAL SOCIETY, AND OF THE ROYAL 



PHYSICAL SOCIETY OF EDINBURGH ; HONORARY 



MEMBER OF THE BIOLOGICAL SOCIETY 



OF PARIS; 



OIBECTOB OF THE NATURAL HISTORY DEPARTMENTS OF THE BRITISH MUSEUM; FULLERIAN PROFESSOR 



OF PHYSIOLOGY IN THE ROYAL INSTITUTION OF GREAT BRITAIN. 



WITH THE CO-OPERATION OF 



ADAM SEDGWICK, M.A., F.R.S., 



FELLOW AND TDTOB OF TRINITY COLLESE, CAMBRIDGE; 



W. F. R. WELDON, M.A., F.R.S., 



SYDNEY J. HICKSON, M.A., F.R.S., 



BEYER PROFESSOR OF ZOOLOGY IX THE OWEXS COLLEGE, MANCHESTER. 



WITH LITHOGRAPHIC PLATES AND ENGRAVINGS ON WOOD. 



LONDON : 



J. & A. CHURCHILL, 7, GREAT MARLBOROUGH STREET. 



1900. 



Adlard and Son,] 



[Bartholomew Close. 



