54 University of California Publications in Geology [ VoL - 7 



is found mixed in with a very much cross-bedded sandstone. 

 The sandstones, especially toward the top, are vivianitic, but 

 are not so blue as those seen in the division above. The Lower 

 Division may be considered a shallow water or strand deposit. 



In the section to the west of Kirker Creek, about two hundred 

 and fifty feet above the base of the Lower Division and above 

 a medium fine to shaly, fossiliferous sandstone, is about a hun- 

 dred feet of coarse, angular-grained, tuffaceous, massive sand- 

 stone, which is quite conglomeratic at the base, and very much 

 cross-bedded toward the top. There is a strong suggestion that 

 these cross-bedded sandstones are terrestrial in origin, and are 

 possibly sand-dune material. 



Fauna of Lower Division. — The following species of inverte- 

 brates were obtained from the Lower Division of the San Pablo 

 series : 



Astrodapsis tumidus Remond. 

 Scutella gabbi Remond. 

 Astyris richthofeni Gabb. 

 Balanus, sp. 



Calliostoma splendens Carpenter. 



Calyptraea costellata Conrad. 



Calyptraea filosa Gabb. 



Cardium eorbis Martyn? 



Cerithium, sp. ? 



Chama pellueida Broderip. 



Chionella neweomboniana Gabb. 



Chione, sp. indet. 



Corbieula, n.sp. 



Crepidula rugosa Nuttalli. 



Crypt oniya ovalis Conrad. 



Dosinea, n. s. 



Littorina remondi Gabb. 



Littorina, sp. a. 



Lunatia lewisii Gould. 



Maeoma, n.sp.. Conrad. 



Metis alta Conrad. 



Modiolus multiradiatus Gabb. 



Mytilus eoalingensis Arnolil. n. var. 



Nassa mendiea Gould. 



Oeinebra lurida var. aspera Baird. 



Olivella pedroana Conrad. 

 Ostrea lurida Carpenter. 

 Ostrea titan Conrad. 

 Ostrea vespertina var. sequens ? 



Arnold. 

 Panopea estrellana Conrad. 

 Panopea generosa Gould. 

 Paphia staminea Conrad. 

 Pecten pabloensis Conrad. 

 Peeten crassieardo Conrad. 

 Pecten discus Conrad. 

 Phacoides tenuisculpta Carpenter. 

 Pholas, sp. ? 



Platydon cancellatus Conrad. 

 Pleurotoma, n.sp.? 

 Saxidomus nuttalli Conrad. 

 Schizodesma abscissa Gabb. 

 Siliqua patula var. nuttalli 



Conrad. 

 Solen, n. sp. 

 Spisula albaria Conrad. 

 Spisula eatilliformis Conrad. 

 Thais eanalculata Duclos. 

 Tresus nuttalli Conrad. 



The most common species in the Lower Division of the San 

 Pablo series are : Metis alta, Mytilus eoalingensis, n. var., Modiolus 



