18 



CALIFORNIA ACADEMY OF SCIENCES. 



is represented by the strata of San Pedro and Deadman Island. The writer, there- 

 fore, proposes the name San Pedro Series for the series of Pleistocene strata at San 

 Pedro, including the lower and upper formations, as described in the present paper. 

 Lower San Pedro Series. — A stratum of gray sandstone rests unconformably on 

 the brown Pliocene sandstone of Deadman Island. (See diagram B, PL XXII.) 

 In some places the sand is soft; in others it has been cemented until it is very hard. 

 The soft parts are not fossiliferous, as a rule, while the hard parts are made up in 

 some places almost wholly of beautifully preserved fossils. One locality in particular 

 on the west side of the island, near the north end, is filled with finely preserved 

 specimens. Parts of this bed are very hard, making it almost impossible to get the 

 shells out, while other parts are so soft that the shells can be removed from the 

 matrix with the fingers. This stratum varies in thickness from four to ten feet on 

 the west side to nearly twenty feet on the east side of the island. There seems to be 

 little indication of bedding planes in this stratum. The general dip is to the north. 

 On account of its lying unconformably on the Pliocene, being of different lithological 

 composition, and containing a fauna of which a great number of species have never 

 been found in the Pliocene, this horizon is designated in the present paper as the 

 lower San Pedro series, or the lower part of the Pleistocene. The following species 

 have been obtained from the lower San Pedro gray sand stratum of Deadman Island: 



List of the Fossils of the Lower San Pedro Beds (Lower Pleistocene) of 



Deadman Island. 



(P indicates species living at San Pedro; N indicates species living only north of San Pedro; S indi- 

 cates species living only south of San Pedro; E indicates extinct species or those not known as living.) 



PELECYPODA. 



Amjulus buttoni, P 

 Anomia latnpe, P 

 Bornia retifcra, N 

 Callisla var. pedroana, E 

 Cardium corbis, N 

 C'ardi'im proci'.rum, S 

 Chama prllucida, P 

 Clidiophora pttnclala, P 

 C'ooperella subdiaphana, P 

 C'orbula luteola, P 

 Cryplomya caH/ornica, P 

 Cumingia callfornica, P 

 Diplodonta orbdla, P 

 Donax cali/ornica, P 

 Donax lavigata, P 

 Kellia laperousii, V 

 Kellia suborbicularis, P 

 Kf.nnr.rlia bicarinaia, N 

 Keimtrliajilosa, N 

 Lavicardium aubiitrialum, I 

 Lazaria subquadrala, V 

 Leda fossa, N 

 Leda hamata, P 

 /yirfa var. prmcursor, N 

 Le.da Caphria, P 



Lima dehiscens, P 

 Lucina acutiUncata, 

 Lucina California, 

 Lucina nuttalli, P 

 Lyonsia californica, 

 Macoma catcarea, J 

 Macoma iiujuinata, 

 Macoma nasuta, P 

 Macoma aecta, P 

 Macoma yoldiformis, 

 Mactra falcata, P 

 Metis alia, P 

 Modiola fornicala, 

 Modiola recta, P 

 Moerella salmoma, 

 Mytilus i-dulis, P 

 Mytilimeria nuttalli, 

 Neara pectinata, P 

 Nucula castrensis, V 

 Nucula supraslriala, 

 Oslrea lurida, P 

 Panopea generosa, P 

 Pecten caurinus, N 

 Pectr.it hnslatns, P 

 Peclf'.n hericeus, N 



P 

 P 



N 



N 



Pecten var. strategus, N 

 Pecten jordani, E 

 Pecten latiauritus, P 

 Pecten var. monotimeris, P 

 Petricola carditoides, P 

 Petricola denliculata, S 

 Protocardia ccntifilosa, P 

 Psephis salmonea, N 

 Psephis tanlilla, N 

 Raeta undulata, P 

 Saxidomus aratus, P 

 Semele var. montereyi, N 

 Septifer bifurcatus, P 

 Siliqua lucida, P 

 Solen rosaceus, P 

 iSolin sicarius, P 

 Tapes staminea, P 

 Tellina bodegensis, P 

 Tivela crassatclloides, P 

 Vcnericardia barbarensis, I 

 Vtnrricardia ivnlricosa, N 

 Venus simillima, P 

 Verticordia novcmcostata, 1 

 Yoldia scissurata, P 



