220 University of California Publications in Zoology  {Vou.14 
the Golden Gate. Nevertheless the relatively small percentage of forms 
common to the two contiguous regions is noteworthy. A number of 
the forms listed below were rarely taken. Such species obviously 
have little significance in such a study. Therefore it has seemed ad- 
vantageous to prepare a list of the more common species. 
MoLiuscan FAUNA OBTAINED WITHIN SAN FRANCISCO Bay 
Acmaea patina Eschscholtz* 
Aecmaea persona Eschscholtz* 
Adula stylina Carpenter* 
Acteocina cerealis (Gould) ? 
Anomia peruviana d’Orbigny* 
Area transversa Say* 
Calliostoma costatum (Martyn) * 
Cardium corbis (Martyn) 
Columbella gausapata (Gould) 
Crepidula convexa Say* 
Crepidula nivea Adams 
Entodesma saxicola (Baird) * 
Epitonium hindsi (Carpenter) * 
Ischnochiton dentiens (Gould) * 
Fissuridea aspera (Eschscholtz) * 
Gemma gemma var. purpura Lea* 
Hinnites giganteus Gray* 
Ilyanassa obsoleta (Say) * 
Kellia laperousi (Deshayes) * 
Lasaea rubra (Montagu) * 
Lacuna porrecta Carpenter 
Lacuna unifasciata Carpenter* 
Lacuna variegata Carpenter* 
Leda taphria Dall 
Littorina planaxis (Nuttall) * 
Littorina scutulata Gould* 
Lyonsia californica Conrad* 
Macoma balthica (Linnaeus) 
Macoma inquinata (Deshayes) 
Macoma nasuta (Conrad) 
Margarites pupilla (Gould) * 
Modiolus politus Verrill and Smith? 
Modiolus rectus Conrad* 
Monia macroschisma (Deshayes) * 
Mopalia ciliata Sowerby* 
Mopalia kennerleyi var. swani 
Carpenter* 
Mopalia muscosa Hinds 
Mopalia wosessenski Middendorft* 
Murex (Ocinebra) interfossata 
(Carpenter) ? 
Murex (Ocinebra) lurida 
(Middendorff) * 
Mya arenaria Linnaeus 
Mya (Cryptomya) californicus 
Conrad : 
Mytilus californicus Conrad* 
Mytilus edulis Linnaeus 
Nassa fossata (Gould) 
Nassa perpinguis Hinds 
Nassa mendica Gould 
Odostoma franciscana Bartsch 
Olivella biplicata Sowerby* 
Olivella intorta Carpenter 
Ostrea elongata Solander* 
Ostrea lurida Carpenter 
Paphia staminea (Conrad) 
Paphia tenerrima (Carpenter) * 
Pecten latiauritus Conrad* 
Petricola carditoides (Conrad) * 
Phacoides tenuisculptus (Carpenter) 
Pholadidea penita (Conrad) * 
Pholas pacificus Stearns* 
Polinices draconis (Dall) 
Polinices lewesi (Gould) 
Psephidia ovalis Dall 
Saxicava arctica (Linnaeus) * 
Saxicava pholadis (Linnaeus) 
Saxidomus nuttalli Conrad* 
Schizothaerus nuttalli (Conrad) * 
Siliqua nuttalli (Conrad) 
Spisula catilliformis Conrad* 
Solen sicarius Gould 
Tegula funebrale (A. Adams) * 
Tellina bodegensis Hinds* 
Tellina buttoni Dall 
Tellina salmonea (Carpenter) 
Tonicella lineata (Wood) * 
Trachydermon raymondi Pilsbry* 
Thais emarginata var. ostrina 
(Gould) 
Thais lamellosa (Gmelin) 
Turbonilla franciscana Bartsch 
Turris incisa (Carpenter) * 
Urosalpinx cinereus (Say) * 
Xylotrya, sp. 
Zirfaea gabbi Tryon 
. 
