QUARTERLY^ JOURNAL 



MICROSCOPICAL SCIENCE: 



EDITED BY 



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



Sonorary Felloio of Exeter College, Oxford, and Deputy Linacre Professor of Human 

 and Comparative Anatomy in the University of Oxford. 



WITH THE CO-OPEEATION OF 



E. KLEIN, M.D., F.R.S., 



Lecturer on General Anatomy and Physiology in the Medical School of 

 St. Bartholomeio's Hospital, London ; 



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



Fellow and Assistant-Lecturer of Trinity College, Cambridge ; 



AND 



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



Late Fellotv of St. John's College, Cambridge ; Professor in the Victoria University ; 

 Beyer Professor of Zoology in the Owens College, Manchester. 



VOLUME XXXII.— New Series. 



LONDON: 

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



1891. 



