TABLE OF CONTENTS. 



Page. 



Introduction 1 



Classitication of the Asteroidea 4 



History of systematic work on North Pacific Aeteroidea 5 



Distribution and relationships of North Pacific Asteroidea 10 



Systematic discussion of the fauna 16 



Key to the orders of Aeteroidea 16 



Key to the known families of Phanorozonia 17 



Characters used in the classification of Phanerozonia 18 



Family Porcellanasteridae 22 



Key to the known genera of Porcellanasterida; 23 



Subfamily Porcellanasterina? 23 



Genus Eremicastcr 23 



Subfamily Ctenodiscinse 31 



Genus Ctenodiscus 3I 



Family Astropectinidse 37 



Key to the known genera of Astropectinidas 39 



Genus Leptychaster 42 



Genus Astropecten 55 



Genus Psilaster 71 



Genus Thrissacantkias 78 



Genus Dipsacaster 85 



Genus Dytaster lOi 



Family Luidiidae 105 



Genua Luidia 105 



Family Benthopectinidse 120 



Key to the known genera of Benthopectinidse 120 



Genus Pectinaster 122 



Genus Luidiaster 127 



Genus Nearchaster .' 132 



Genus Myonotus 140 



Genus Benthopecten 142 



Family Odontasteridse 153 



Key to the known genera of Odontasteridae 153 



Genus Odontaster I54 



Family Goniasteridse 158 



Notes on certain genera of the Goniasteridse 163 



Key to the known genera of Goniasteridae 169 



Subfamily Mimasterinse 175 



Genus Gephyreaster 175 



Subfamily Pseudarchasterinae 179 



Genus Psevdarchasler 179 



Subfamily Goniasterinse 196 



Genus Mediaster 196 



Genus Ceramaster 204 



Genus Cladaster 221 



