Transcriber's note: Spelling and punctuation inconsistencies have been harmonized. Obvious printer errors have been repaired. Italic text has been marked with _underscores_. The symbol for male has been rendered as [M] and for female as [F]. The Cambridge Manuals of Science and Literature EARTHWORMS AND THEIR ALLIES CAMBRIDGE UNIVERSITY PRESS London: FETTER LANE, E.C. C. F. CLAY, MANAGER [Illustration] Edinburgh: 100, PRINCES STREET London: WILLIAM WESLEY & SON, 28, ESSEX STREET, STRAND Berlin: A. ASHER AND CO. Leipzig: F. A. BROCKHAUS New York: G. P. PUTNAM'S SONS Bombay and Calcutta: MACMILLAN AND CO., LTD. _All rights reserved_ EARTHWORMS AND THEIR ALLIES BY FRANK E. BEDDARD M.A. (Oxon.), F.R.S., F.R.S.E. Cambridge: at the University Press New York: G. P. Putnam's Sons 1912 Cambridge: PRINTED BY JOHN CLAY, M.A. AT THE UNIVERSITY PRESS _With the exception of the coat of arms at the foot, the design on the title page is a reproduction of one used by the earliest known Cambridge printer, John Siberch, 1521_. PREFACE The importance of earthworms in questions relating to geographical distribution is so universally admitted that it seemed to me convenient to embody in a short volume the principal facts. It became necessary in order to accomplish this task in an adequate fashion to preface the distributional facts with some anatomical and zoological data. I have reduced this section of the book to a minimum and I trust that the illustrations will enable the reader, who is not specially acquainted with the structure of these animals, to obtain an idea of their general features and variability in external character and internal anatomy. While the use of technical terms is inevitable in presenting such details, it will be found, I think, that a reference to the figures will render them intelligible. Since this volume mainly deals with the phenomena of distribution, I have included in my survey nearly all of the usually admitted genera of worms, particularly of the terrestrial forms, which are in the light of our present knowledge the more important in considering this subject. F. E. B. ZOOLOGICAL SOCIETY OF LONDON. _December_, 1911. CONTENTS CHAP. PAGE I. Structural and Systematic 1 II. Mode of Life 43 III. The external features of Earthworms and their relation to habit and environment 59 IV. Sense Organs and Senses of Earthworms 64 V. Relative frequency of Earthworms in different regions of the World 70 VI. Peregrine forms 96