18 



CALIFOUNIA ACADKMY OF 8CIENCKS. 



is represciiieil l>y till' -tnitii of Sail IV-dro and Dradiuaii Island, 'riic writer, there- 

 fore, proposes tlie name San IVdro StMies for the series of Pleistocene strata at San 

 Pedro, inchuling the K)wer and upper formations, as described in the present paper. 

 Lower San Pedro Series. — A stratum of f;;ray sandstone rests unconformably on 

 the brown Pliocene sandstone of Deadman Island. (See diagram J>, PI. XXI I.) 

 In some places the .sanil 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 difloront lithological 

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

 l)een 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 olUained from the lower San Pedro gray sand stratum of Deiulmaii Island: 



List of the Fossils ok the Lowek San Pedko Beds (Lower Pleistocene) of 



Dkad.man Island. 



(P indicates si>ccie8 liviug at Sau Fcdro; N indicates species living oulj- north of San Pedro; S indi- 

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



Anomia tampe, V 

 Bornia retifrra, N 

 Callitta Tar. pedroana, £ 

 Cardinm corbis, N 

 Cardivm procTum, S 

 Chnmn prllwida, V 

 Clidiophorn punctata, P 

 CooptreUa suhdia/ihana, V 

 C'orhula liitfola, P 

 Cryptomya rali/oniica, P 

 Cumingia cali/orniea, P 

 Diplodonta orbrlta, P 

 Donax calif ornica, P 

 Donax liTvigala, P 

 Kellia taperoufiii, P 

 K^ltia itihorhicularu, V 

 Krnn'rlia hicarinala, N 

 K^HWrliaJilo'o, N 

 Lttricardium suhHrialnm, 1 

 Lazaria 8iib*juadrata, P 

 Leda/oMO, X 

 Lfda hamata, P 

 Lrda var. pmcumor, N 

 Leda laphria, P 



PELECYPODA. 



Lima dehiicenn, P 

 Lucina acutilincata, P 

 Lucitia cali/omica, P 

 Lucina nuttalli, P 

 Lyontia californira, P 

 Macoma calcarea, N 

 Afacoma inrjuitiala, P 

 Macoma noiula, P 

 Macoma nerla, P 

 Macoma yoldiformis, V 

 Mactra falcata, P 

 Metis alia, P 

 Modiota fomicala, N 

 Modiola recta, P 

 Moerella salmonca, N 

 Mytilua rdulis, P 

 Mytitimeria nullalli, P 

 Ncara jvctinata, P 

 Sucula c'istrensit, P 

 yucula suprattriata, N 

 Oslrea lurida, P 

 Panopca gcnerosa, P 

 Pecten caurinus, N 

 Pecten haslatus, P 

 Pecten hericeux, N 



Pecten var. Hratcyus, N 

 Pecten jordani, E 

 Pecten latiauritus, P 

 Pecten var. monolimeris, V 

 Petricola carditoides, P 

 Pelricola dinlicuUUa, S 

 Protocardia cntijUosa, V 

 Psephis salmonea, N 

 Pscphis tantilla, N 

 Raela undulata, P 

 Sazidomus aratus, P 

 Semele var. montereyi, N 

 Septifcr bi/urcatut, P 

 Siliqua lucida, P 

 Sokn rosacius, P 

 Sohn sicarius, P 

 Tapen utaminea, P 

 Tellina bodegensis, P 

 Tivela crassairlloides, P 

 Venericardia barbarensin, P 

 r< turicardia ventricota, N 

 Venus simiUima, P 

 Verlicordia novemcostata, V 

 Yotdla scisnurala, P 



