List of TextFigures ..... Introduction ....... Historical Accou.nt of the Chaetopod.v, with Speci.l Reference to the Polychaeta and their Classification Arenicolidae ....... Arenicola Lamarck, emend. A General Account of the Genus Arenicola External Characters External Apertures .... Chaetae ...... Gills Coelom and Coelomic Septa Alimentary Canal : Burrowing . Nervous System and SenseOrgans Nephridia ..... Reproductive Organs Development ..... PostLarval Stages, with a Discussion of the Genus Chj)ne?iidcs PostLarval Stages of A. marina ,, ,, ,, A. cristata „ ,, ,, A. assimilis var. ajfi ,, ., ,, A. ccaudata ,, ,, ,, A. hranchialis . Separation of the Genus Arenicola into Sections and Species The Caudate Section of the Genus Arenicola (with a Key to th Caudate Species) ....... The Ecaudate Section of the Genus Arenicola (with a Key to the Ecaudate Species) Arenicola marina (Linnaeus) . Arenicola loveni Kinberg, emend. Arenicola cristata Stimpson Arenicola glacialis Murdoch Arenicola junilla Quatrefages . Arenicola assiynilis Ehlers, and var. affinis Ashworth. Arenicola ecaudata Johnston . Arenicola hranchialis Audouin and Edwards Branchiomaldane Langerhans ... Branchiomahlanr vinccnti Langerhans The Interrelationships of the Members of the Family Arenicolidae The Affinities of the Arenicolidae Systematic Index to the Arenicolidae Gener.l Index ....... Description of Plates IXV .... 1>A«E viixi 1 2529 32 3338 39 55 6163 66 7172 73 75 77798080 8182 83 84 86 103 105 111 114 123 132 138
B , M (N.H.) A (gxiiiB^ T/i7s Catalogtie (Utueeum ((Uaturaf J^^^torj) is of No oCt) of the 25 Chaetopoda, copies Part of /., Arenicolidie, printed on Special paper PRESENTED BY ^bc n:ru0tec0 OF THE BRITISH MUSEUM c* O : 311 6?6« CATALOGUE 111?, OF THE '-^'^''t H x\ E T O P O D A IN BEITISH THE MUSEUM (NATUIIAL HISTORY) A POTjYCHAETA: PART L— AREXICOLIDAE BY J H ASHWOETH, D.Sc, Lecturer on Incertebrtttc Zoology in the Unieersity of Ediiihimjh LONDON PRINTED BY ORDER OF THE TRUSTEES OF THE BRITISH MUSEUM SOLD BY LoKGMANS, Grekn & Co., 39, Paternostku Row, E.G B QuARiTCH, 11, Grafton Street, New Bond Street, W DoLAU & Co., Ltd., 37, Soho Square, W AND AT the British Museum (Natural History), Cromwell Road, S.\V 1912 {All rights reserved.) ^vr'rs: !i : LONDON PRINTEP BV WILLIAM CLOWES AND SONS, LIMITED, DUKE STREET, STAMFORD STREET, S.E., AND GREAT WINDMILL STREET, W PEEFACE The present work, which was undertiikeu at the suggestion of the Kay Lankester, K.C.B., former Director, Sir E a small proportion Catalogue of tlie ground of the to Chaetopoda or even of the Polychaeta " l*art Although the volume appears as catalogue, its F.R.S., covers l)ut he gone over in making a selection for first tlie circumstance, depending on the fact I " of tliat a was place more general a fortuitous Dr J H Ashworth, the author, had already devoted special attention to the Arenicolidae when not the idea was chosen beginning first because But projected as circumstances thought advisa])le to The Family was supposed it to in question w^as thus come have plnced it naturally the at there, it has been devote some pages to an introductory survey of the history and classification of the Chaetopoda, and in particular of the Polychaeta by the author Morphological characters are largely employed in characterising the species Mr r Jeffrey Bell, whose official duties in the Museum include the care of the specimens of Chaetopoda, has devoted mucli time to the editing of this A'^olume The continuation at present provided of the series of for, but it is volumes on Chaetopoda is not hoped that opportunities will present themselves from time to time of continuing the series which has been begun by Dr Ashworth SIDNEY V HABMEK, Keeper of Zoology British Museum (Natural History), London, S.W., November, 1912 T.IBLE OF CONTENTS 1>A«E List of Text-Figures Introduction vii xi Historical Accou.nt of the Chaetopod.v, with Speci.\l to the Polychaeta and their Classification Reference Arenicolidae 25 Arenicola Lamarck, emend A General Account of the Genus Arenicola 29 32 33 38 39 55 External Characters External Apertures Chaetae Gills Coelom and Coelomic Septa Alimentary Canal Burrowing Nervous System and Sense-Organs Nephridia Reproductive Organs : Development 61 Post-Larval Stages, with a Discussion of the Genus Chj)ne?iidcs Post-Larval Stages of A marina A cristata A assimilis var ajfi A ccaudata , ,, ,, A hranchialis ,, ,, ,, Separation of the Genus Arenicola into Sections and Species The Caudate Section of the Genus Arenicola (with a Key to th ,, ,, ,, „ ,, ,, Caudate Species) The Ecaudate Section of the Genus Arenicola (with a Key 83 to the Ecaudate Species) Arenicola marina (Linnaeus) Arenicola loveni Kinberg, emend Arenicola cristata Stimpson Arenicola glacialis Murdoch Arenicola j^unill a Quatrefages Arenicola assiynilis Ehlers, and var affinis Ashworth Arenicola ecaudata Johnston Arenicola hranchialis Audouin and Edwards Branchiomaldane Langerhans Branchiomahlanr vinccnti Langerhans The Inter-relationships of the Members of the Family Arenicolidae The Affinities of the Arenicolidae 63 66 71 72 73 75 77 79 80 80 81 82 84 86 103 105 111 114 123 132 138 147 147 156 159 Systematic Index to the Arenicolidae 163 Gener.\l Index 165 Description of Plates I-XV 171 ! CAT CHAETOPODA BRIT MUS Nvx: Plate XI Gr Br' AKMaxwell.de! E Wilson Cambridge , GAT OHAETCPODA BRIT MUS.I PI at e XII \ Cirri Aci • Neur AK MaxweU.del £ Wilson /3ajnbrk]Qe CAT CKABTOPODA BRIT MUS Plate I CE A.K Maxwell del Xlil SP E WilBon.Caabndge CAT, GHAETOPODA AX Maxwoli t J H Ashvrorth.del BRIT MUS.I Plate XIV E 'WilBon, Cambridge UAr, l;H/\UT UPODA BKI'i' [vlUi ^1 ^, ,/?ft Mph.FD Nph.FD ^f^\"iv "!^ -BLV Ovary Ovary Ves 52.XIO ilii.^ AK.Maxwell.del C WilGon.Canibridge ... Museum include the care of the specimens of Chaetopoda, has devoted mucli time to the editing of this A'^olume The continuation at present provided of the series of for, but it is volumes on Chaetopoda. .. Collections of Arenicola in the Museums of Berlin, Paris, Cambridge (Mass.) and the Smithsonian Institution, together with interesting examples from the Museums of Copenhagen, Dublin, Hamburg,... stages in the growth of knowledge regarding the Chaeto- poda, and their classification, and to schemes of classification proposed the of the worms which form the subject of the present especially indicate