Advances in PARASITOLOGY VOLUME 5 This Page Intentionally Left Blank Advances in PARASITOLOGY Edited by BEN DAWES Department of Zoology, King's College, University of London, England VOLUME 5 1967 ACADEMIC PRESS London and New York ACADEMIC PRESS INC. (LONDON) LTD. Berkeley Square House Berkeley Square London, W. 1 U .S. Erlitioir puhlisli~~l by ACADEMIC PRESS INC. I 1 1 Fill11 Avenue New York, New Yoi-k 10003 C'op!riglit I(') 1067 by ACADEMIC PRESS INC. (LONDON) LTD. Second printing 197 1 All Rights Reserved N o part of this book may be reproduced in any form, by photostat, microfilm, or any other means, without writtep permission from the publishers Lihrnry of Cony-esb Catalog Card Number: 62-22 124 SBN: -1 2-39 1 705.2 CONTRIBUTORS TO VOLUME 5 ANNBISHOP, Molteno Institute, University of Cambridge, England (p. 93) P. C. C. GARNHAM, London School of Hygiene and Tropical Medicine, London, England (p. 139) CECILA. HOARE,Wellcome Historical Medical Museum and Library, London, England (p. 47) LEONJACOBS, US. Department of Health, Education and Welfare, Public Health Service, National Institutes of Health, Division of Biologics Standards, Bethesda, Maryland, U.S.A. (p. 1) W. L. NICHOLAS, College of Veterinary Medicine and Department of Zoology, University of Illinois, Urbana, Illinois, U.S.A. (p. 205)* MARIETTA VOGE,Department of Medical Microbiology and Immunology, UCLA School of Medicine, Los Angeles, California, U.S.A. (p. 247) * Present address: Department of Zoology, Australian National University, Canberra Australia. V This Page Intentionally Left Blank PREFACE In this volume of Advances in Parasitology more than usual emphasis has been placed on the Protozoa, but many readers will agree that this is equitable. Of the twenty-four contributions already published in four volumes, five dealt with protozoan parasites, five with trematodes, two with cestodes, six with nematodes, four with helminths in general, one with snail control in trematode disease and one with feeding in ticks. In this the fifth volume, four contributors deal with various Protozoa, one with post-embryonic developmental stages of cestodes and one with the biology of the Acanthocephala. In his review on Toxoplasma and toxoplasmosis, Leon Jacobs has been concerned mainly with work published during the past three to four years, earlier work providing historical perspective. He begins with electron microscopy and goes on to discuss in some detail mechanisms of transmission, serology, the association of Toxoplasma with certain diseases, epidemiology, pathology, immunity, physiology and therapy. The study of fine structure of trophozoites of Toxoplasma from in vivo and in vitro sources has cleared up some points about reproduction. The rosette-like bodies which appear repeatedly are incompletely separated daughter parasites developing by a special form of schizogony (“endodyogeny”), which occurs also in encysted forms. Matters concerning the cytostome, “toxonemes” and other organelles are also clarified by discussion. The cyst develops within a vacuole in a host cell, and it may attain an enormous size without rupturing the cell as does a rapidly growing mass of trophozoites. The transmission of Toxoplasma gondii to man and animals is widespread but sources of infection are difficult to recognize, except in the case of carnivores which eat the raw meat of infected sheep or swine. The investigation of possible invertebrate carriers of cysts or vectors of trophozoites has placed nematodes under suspicion. Widespread toxoplasmosis in sheep both in this country and far abroad may be explicable in terms of transmission by nematodes in their eggs. However, the hygienic habits of felines militate against the view