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University of California Publications in Zoology [Vol. 13 



Species Occurring in Group 1: Pure Mud 



Cardium corbis 

 Macoma balthica*, 

 Macoma nasuta* 

 Mya arenaria* 

 Mya California* 

 Mytilus edulis* 

 Ostrea lurida 



Paphia staminea 

 Pholas pacificus 

 Psephidia ovalis 

 Zirfaea gabbi 

 Epitonium hindsi 

 Odostomia franciscana 

 Turbonilla franciscana 



Species Occurring in Groups 2 and 4 : Mud and Sand 



Cardium corbis* 



Gemma gemma var. purpura* 



Macoma balthica* 



Macoma inquinata 



Macoma nasuta* 



Mya arenaria 



Mya California* 



Mytilus edulis* 



Ostrea lurida 



Phacoides tenuisculptus* 



Pholas pacificus 



Psephidea ovalis 



Schizothaerus nuttalli 

 Solen sicarius 

 Tellina buttoni* 

 Tellina salmonea* 

 Zirfaea gabbi* 

 Crepidula niva* 

 Columbella gausapata 

 Nassa mendiea 

 Nassa fossata* 

 Nassa perpinguis 

 Thais lamellosa* 

 Turbonilla franciscana 



Species Occurring in Group 3: Mud and Shells 



Cardium corbis 



Gemma gemma var. purpura^ 



Macoma inquinata 



Macoma nasuta* 



Mya arenaria* 



Mya California* 



Modiolus, cf. rectus 



Mytilus edulis 



Ostrea lurida 



Paphia staminea 

 Psephidea ovalis 

 Zirfaea gabbi* 

 Columbella gausapata 

 Epitonium hindsi? 

 Nassa fossata? 

 Nassa mendiea* 

 Thais lamellosa 

 Turbonilla keepi 



Species Occurring in Group 5: Pure Sand 



Mytilus edulis* 

 Phacoides tenuisculptus* 

 Psephidea ovalis* 



Tellina buttoni* 

 Turbonilla franciscana* 



Species Occurring in Group 6: Sand and Gravel 



Cardium corbis 

 Hinnites giganteus 

 Macoma balthica 

 Macoma inquinata 

 Macoma nasuta 

 Monia macroschisma 

 Mya California 

 Ostrea lurida 



Saxidomus nuttalli 

 Schizothaerus nuttalli 

 Spisula catilliformis 

 Tellina salmonea* 

 Nassa fossata 

 Thais lamellosa 

 Zirfaea gabbi 



Species Occurring in Group 7: Sand and Shells 



Cardium corbis 

 Macoma balthica 

 Macoma inquinata 

 Macoma nasuta 

 Mya arenaria 

 Mya California* 

 Mytilus edulis 

 Ostrea lurida 

 Psephidia ovalis* 



Schizothaerus nuttalli 

 Tellina salmonea 

 Zirfaea gabbi 

 Epitonium hindsi* 

 Epitonium savinea 

 Nassa perpinguis 

 Thais lamellosa 

 Turbonilla keepi 



