1918 ] Packard: Molluscan Fauna from San Francisco Bay 217 
The outside fauna consists of 62 (+ 6?) species, of which 34 are 
pelecypods, 32 are gastropods, and 2 are secaphopods. Forty-six per 
cent of this fauna was not obtained within San Francisco Bay. This 
great difference between the two faunas is not due to depth, but pre- 
sumably to other factors, such as decreased salinity, fluctuating tem- 
peratures, and varied bottom conditions peculiar to partially enclosed 
waters. The mollusks that are restricted in our records to the ocean 
off San Francisco are indicated in the following list of the outside 
fauna by an asterisk. 
MOoLLuUSCAN FAUNA OBTAINED IN THE OPEN OCEAN Orr SAN FRANCISCO 
Acila ecastrensis (Hinds) * 
Actaeon punctocoelatus (Conrad) * 
Acteocina cerealis (Gould)* 
Astralium triumphans Philippi* 
Barleeia subtenuis Carpenter* 
Bathytoma carpenteriana Stearns* 
Bittium subplanulatum Bartsch* 
Cadulus fusiformis Philippi* 
Cancellaria crawfordiana Dall* 
Cardium corbis (Martyn) 
Cardium (Protocardia) centifilosum 
Carpenter* 
Chrysodomus tabulatus Baird* 
Columbella gausapata Gould 
Crepidula nivea Adams? 
Cuspidaria californica Dall* 
Dentalium indianorum Linnaeus* 
Epitonium sawinae (Dall) 
Eunaticina oldroydi (Dall) 
Hinnites giganteus Gray 
Lacuna porrecta Carpenter 
Leda hamata Carpenter* 
Leda taphria Dall 
Lyonsia californica Conrad 
Macoma indentata Carpenter* 
Macoma inquinata Deshayes? 
Macoma nasuta (Conrad) ? 
Macoma yoldiformis Carpenter* 
Mangilia angulata Carpenter* 
Marcia subdiaphana (Carpenter) * 
Melanella (Eulima) micans 
(Carpenter) * 
Modiolus politus Verrill and Smith 
Murex (Ocinebra) interfossa 
(Carpenter) * 
Mya arenaria Linnaeus 
Mya (Cryptomya) californica 
(Conrad) 
Mytilus edulus Linnaeus 
Nassa fossata (Gould) 
Nassa mendica Gould 
Nassa perpinguis Hinds 
Nucula tenuis (Montagu) * 
Odostomia franciseana Bartsch 
Olivella intorta Carpenter 
Olivella pedroana Conrad* 
Ostrea lurida Carpenter 
Pandora filosa (Carpenter) * 
Paphia staminea (Conrad) 
Phacoides annulatus (Reeve) * 
Phacoides tenuisculptus (Carpenter) 
Polinices draconis (Dall) 
Polinices lewisi (Gould) 
Psephidia ovalis Dall 
Siliqua nuttalli (Conrad) 
Solen sicarius Gould 
Tellina buttoni Dall? 
Tellina carpenteri Dall* 
Tellina salmonea (Carpenter) 
Thais emarginata var. ostrina 
(Gould) 
Thais lamellosa (Gmelin) 
Thyasira gouldi (Philippi) * 
Turbonilla keepi Dall and Bartsch* 
Turbonilla franciseana Bartsch* 
Turris (Bela) tabulata Carpenter* 
Turris incisa Carpenter* 
Turris perversa (Gabb)* 
Volvula cylindrica Carpenter* 
Xylotrya, sp. 
Yoldia cooperi Gabb* 
Yoldia ensifera Dall* 
Zirfaea gabbi Tryon 
