vi CONTENTS 



ISOPOD CRUSTACEA PART II. THE SUB-ORDER VALVIFERA. FAMILIES: 

 IDOTEIDAE, PSEUDIDOTHEIDAE AND XENARCTURIDAE FAM.N. With a 

 supplement to Isopod Crustacea, Part I. The Family Serolidae (published 6th September 1957) 



By Edith M. Sheppard 



Introduction pcg^ i43 



Acknowledgement i44 



Station List i44 



Morphology of the Valvifera i47 



Systematic Account i49 



Family Idoteidae i49 



Family Pseudidotheidae i73 



Family Xenarcturidae fam.n 182 



Summary 187 



References 187 



The Family Serolidae 189 



Station List 190 



Summary ........•■•••••• i97 



References ^97 



Plates VIII, IX following page igS 



THE DISTRIBUTION OF THE CHAETOGNATHA OF THE SOUTHERN OCEAN 

 (published nth April 1958) 



By P. M. David 



Introduction P«,?« 201 



Acknowledgements 201 



Material and Methods 201 



A Summary of the Species of Chaetognatha found in the Southern Ocean . . .203 



I. 'Endemic' species 203 



II. Species common to other regions ........... 205 



III. Exotic species 207 



IV. Doubtful species 209 



Vertical Distribution 209 



The Segregation of Species 218 



Winter Distribution 221 



The Distribution of the Mature Stages 221 



The Pattern of Distribution 223 



Summary 223 



