1^1 
New Series, No. 246 (Vol. 62, Part 2). Price 10s. 6d. net. 
Subscription per volume (of 4 parts) 42s. net. 
FEBRUARY, 1917. 
THE 
J 
QUARTERLY JOURNAL 
OF 
MICROSCOPICAL SCIENCE. 
EDIT K I) HY 
Sir RAY LANKESTER, K.C.B., M.A., D.Sc., LL.D., F.R.S., 
HONORARY FELLOW OK EXETER COLLEGE AND HONORARY .-STUDENT OF CHRIST CHURCH, OXFORD; 
MEMBER OK THE INSTITUTE OK FRANCK (ASSOClfe ETRANGER DE I.’aCADEMIE DES SCIENCES); 
CORRESPONDENT OK THE IMPERIAL ACADEMY OK SCIENCES OF 8T. PETERSBURG, AND OF THE 
ACADEMY OF SCIENCES OK PHILADELPHIA, AND OK THE IlOYAI. ACADEMY OK SCIENCES 
ok turin; foreign member of tub roial society ok sciences ok 
GOTTINGEN, AND OK THE ROYAI. BOHEMIAN SOCIETY OK SCIENCES, AND 
OK THE ACADEMY OK THE I.INCKI OK ROME, AND OK THE AMERICAN 
ACADEMY OF ARTS AND SCIENCES OK BOSTON; ASSOCIATE OK TUB 
ROYAI, ACADEMY OF BELGIUM: HONORARY MEMBER l)K THE 
NEW YORK ACADEMY OK SCIENCES, AND OK THE 
CAMBRIDGE P H 1 1,08 O I'll I C A I. SOCIETY, AND OK 
THE ROYAI, PHYSICAL 80CIKTY OK EDIN- 
BURGH, AND OK TUB 
BIOLOGICAL AND 1 ZOOLOGICAL SOCIETIES OF PARIS, AND OK THE CALIFORNIA ACADEMY OK SCIENCES OK 
SAN FRANCISCO, AND OK THE ROYAI. ZOOLOGICAL AND M ALACOLOGIC AI. SOCIETY OK BELGIUM; 
CORRESPONDING MEMBER OF THE 8ENKV.NBERG ACADEMY OF FIl A N KFUIIT A- M ; 
FOREIGN ASSOCIATE OK THE NATIONAL ACADEMY OF SCIENCES. U.8., AND MEMBER OK THE 
AMERICAN PHILOSOPHICAL SOCIETY ; 
HONORARY FELLOW OF THE ROYAL SOCIETY OF EDINBURGH', 
LATE DIRECTOR OK THE NATURAL HISTORY DEPARTMENTS OK THE BRITISH MUSEUM; I, ATE PRESIDENT OF TUB 
BRITISH ASSOCIATION FOR THE ADVANCEMENT OP SCIENCE,' LATE KUI.I.KRIAN PROFESSOR OK 
PHYSIOLOGY IN THE ROYAL INSTITUTION OK GREAT BRITAIN ; 
LATE I, IN ACRE PROFESSOR OF COMPARATIVE ANATOMY AND FELLOW OF MERTON COLLEGE, OXFORD ; 
EMERITUS PROFESSOR OK ZOOLOGY AND COMPARATIVE ANATOMY IN UNIVERSITY COLLEGE, UNIVERSITY OF LOUDON 
WITH THE CO -OPE It ATI ON OK 
SYDNEY J. HICKSON, M.A., F.R.S., 
BKYRR PKOK1C8SOK OK ZOOLOGY IN THE UNIVERSITY OP M A N C II 1C 8 T K K ; 
GILBERT C. BOURNE, M.A., D.Sc., F.R.S., 
I.INACRE PROFESSOR OK COMPARATIVE ANATOMY, AND KICI.LOW OK MERTON COLLEGE, OXFORD 
J. GRAHAM KERR, M.A., F.R.S., 
REGIUS PROFESSOR OF ZOOLOGY IN THE UNIVERSITY OF GLASGOW; 
AND 
E. W. MACBRIDE, M.A., D.Sc., LL.D., F.R.S., 
PROFESSOR OF ZOOLOGY AT THE IMPERIAL COLLEGE OF SCIENCE AND TECHNOLOGY. 
WITH LITHOGRAPHIC PLATES AND TEXT-FIGURES. 
J. & A. CHURCHILL, 
LONDON. 
7 GREAT MARLBOROUGH STREET. 
1917. 
Adlard & Son & West Newman, Ltd.,] 
[London and Dorking. 
