T.IBLE OF CONTENTS 



List of Text-Figures ..... 



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 Sense-Organs 

 Nephridia ..... 



Reproductive Organs 



Development ..... 



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 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 

 Systematic Index to the Arenicolidae 

 Gener.\l Index ....... 



Description of Plates I-XV .... 



1>A«E 



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