New Series. No. 261.] MARCH, 1922. [Volume 66. Part I. 



THE 



QUARTERLY JOURNAL 



OF 



MICROSCOPICAL SCIENCE. 



HONORARY EDITOR : 



Sm RAY LANKESTER, K.C.B., M.A, D.Sc, LL.D, F.R.S. 



EDITOR : 



EDWIN S. GOODRICH, M.A., F.R.S., 



LINACRE PROFESSOR OF ZOOLOGY AND COMI-AKATIVE ANATOMY IN THE UNIVEKSITY OF OXFORD • 



WITH THE CO-OPERATION OF 



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



BEYER PR0FES80B OF ZOOLOGY IN THE UNIVERSITY OF MANCHESTER; 



GILBERT C. BOURNE, M.A., D.Sc, F.R.S.; 

 J. GRAHAM KERR, M.A., F.R.S., 



REGIUS PROFESSOR OF ZOOLOGY IN THE UNIVERSITY OF GLASGOW • 



E. W. MACBRIDE, M.A., D.Sc, LL.D., F.R.S., 



PROFESSOR OF ZOOLOGY AT THE IMPERIAL COLLEGE OF SCIENCE AND TECHNOLOGY ; 



G. P. BIDDER, M.A., ScD. 



WITH LITHOGRAPHIC PLATES AND TEXT-FIGURES. 



OXFORD UNIVERSITY PRESS, 



HUMPHREY MILFORD, AMEN CORNER, LONDON, E.G. 4. 



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