MAY 7 1900 



New Series, No. 169 (Vol. 43, Part 1). 



FEBRUAEY, 1900. 



THE 



Price 10s. 



QUARTERLY JOURNAL 



OF 



MICROSCOPICAL SCIENCE. 



EUITBI) BY 



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



HONORARY FELLOW or EXEIEK COLLEGE, OXI'OU D ; CORR RSPOX DENT OF THE IX 

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

 OF SCIENCES OF PHILADELPHIA; FOREIGN MEMBER OF THE KOVAL 

 SOCIETY OF SCIENCES, AND OF THE ACADEMY OF THE LINCEI OP 

 ASSOCIATE OF THE ROYAL ACADEMY OiF BELGIUM ', HONORARY MEMl 

 OF THE NEW YORK ACADEMY OP SCIENCES* AND OF THE 

 CAMBRIDGE PHILOSOPHICAL SOCIETY, AND OF THE ROYAL 

 PHYSICAL SOCIETY OF EDINBURGH ; HONORARY 

 MEMBER OF THE BIOLOGICAL SOCIETY 



OF PARIS ; 



DIRECTOR OF THE NATURAL HISTORY DEPARTMENTS OF THE BRITISH MUSEUM; F 

 OF PHYSIOLOGY IN THE ROYAL INSTITUTION OP GREAT BRITAIN. 



WITH THE CO-OPERATION OF 



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



FELLOW AND TUTOR OF TRINITY COLLEGE, CAMBRIDGE; 



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



WITH LITHOGRAPHIC PLATES AND ENGEAVINGS ON WOOD. 



LONDON : 



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



1900. 



Adtard and Son,] 



[Bartholomew Close. 



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