14 CONTENTS 



Platyhelminthes (Continued). page 



Nemertinea 77 



Tetrastemma 77 



NEMATHELMINTHES 79 



Ascaris 79 



Trichinella 80 



Metoncholaimus 81 



TROCHELMINTHES : 84 



ROTIFERA 84 



Brachionus 84 



MOLLUSCOIDA 86 



Bryozoa '. 86 



Bugula ." 86 



Plumatella * 88 



Brachiopoda : 89 



Terebratulina 89 



ANNELIDA 89 



Chaetopoda 91 



Nereis virens (Clam-worm) 91 



Autolytus cornutus 95 



Lepidonotus (Polynoe) squamatus 96 



Diopatra cuprea 98 



Chaetopterus 99 



AmphiCrite ornata 100 



Cistenides (Pectinaria) gouldi 101 



Clymenella torquata 101 



Arenicola cristata (Lug-worm) 102 



Parasabella microphthalma 107 



Hydroides 108 



Spirorbis 109 



Lumbricus (Earthworm) 109 



Macrobdella (Leech) 115 



Gephyrea 119 



Phascolosoma 119 



MOLLUSCA 122 



Pelecypoda 124 



Venus mercenaria (Quahog) 124 



Yoldia limatula 133 



Mytilus or Modiolus (Mussels) 134 



Pecten gibbus borealis (Scallop) 136 



Ostrea virginica (Oyster) 137 



Solemya 138 



Mya arenaria (Long Clam) 138 



Ensis directus (Razor-shell Clam) 140 



Cumingia tellinoides 141 



Amphineura 142 



Chaetopleura (Chiton) 142 



Gastropoda 143 



Busycon (Fulgur, Sycotypus) (Whelk) 143 



Cephalopoda 153 



Loligo pealei (Squid) 153 



