JUN 14 1893 



New Series, No. CXXXVI (Vol. XXXIV, Part 4). Price 10s. 



6~3jh APEIL, 1893. 



THE 



QUARTERLY JOURNAL 



OF 



MICEOSCOPICAL SCIENCE. 



EDITED BY 



E. EAT LANKESTER, M.A., LL.D., E.K.S., 



Linacre Professor of Human and Comparative Anatomy, Fellow of JUerton College, and 

 Honorary Fellow of Exeter College, Oxford ; 



WITH THE CO-OPEKATION OF 



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



Fellow and Lecturer of Trinity College, Cambridge ; 



A. MILNES MARSHALL, M.A., D.Sc, M.D., F.R.S., 



Late Fellow of St. John's College, Cambridge ; Professor in the Victoria University ; Beyer Prof essor of Zoology 

 in the Owens College, Manchester . 



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



Jodrell Professor of Zoology and Comparative Anatomy in University College, London ; 

 Fellow of St. John's College, Cambridge. 



WITH LITHOGKAPHIC PLATES AND ENGRAVINGS ON WOOD. 



LONDON: 

 J. & A. CHURCHILL, 11, NEW BURLINGTON STREET. 



MDCCCXCIII. 



Adlard and Son,] 



[Bartliolomew Close. 



