JUN 4 1900 



New Series, No. 170 (Vol. 43, Part 2). 



APRIL, 1900. 

 THE 



Price 10s. 



QUARTERLY JOURNAL 



OF 



MICEOSCOPICAL SCIENCE. 



EDITED BY 



E. EAY LANKESTBR, M.A., LL.D., F.R.S., 



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



AND OF THE IMPERIAL ACADEMY OF SCIENCES OF ST. PETERSBURG, AND OF THE ACADEMY 



OF SCIENCES OF PHILADELPHIA; FOREIGN MEMBER OF THE ROYAL BOHEMIAN 



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



ASSOCIATE OF THE ROYAL ACADEMY OF BELGIUM ; HONORARY MEMBER 



(IF THE NEW YORK ACADEMY OF SCIENCES* AND OF THE 



CAMBRIDGE PHILOSOPHICAL SOCIETY, AND OF THE ROY AL 



PHYSICAL SOCIETY OF EDINBURGH ; HONORARY 



MEMBER OF THE BIOLOGICAL SOCIETY 



OF PARIS; 



DIRECTOR 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.E.S., 



FELLOW AND TUTOR OF TRINITY COLLEGE, CAMBRIDGE; 



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



AND 



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



BEYER PROFESSOR OF ZOOLOGY IN THE OWENS COLLEGE, MANCHESTER. 



WITH LITHOGRAPHIC PLATES AND ENGRAVINGS ON WOOD. 



LONDON: 



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



1900. 



A.dlard and Son,] 



[Bartholomew Close. 



