PLEISTOCKNE FORMATIONS. 



31 



List (if I'llocfne fosxilaj'riiiii Di'ddiiian Ixlaiid — Continued. 



PELECYPODA- 



'ontinued 



Lyonsia californica Conrad. 



Macoma calcarea Gnielin. 



Macouia inquinata Deshayes. 



Marcia subdiaphana Carjjenter (dementia ir 



Mytilimeria nuttalli Conrad. 



Nucula castrenais Hindis. 



Panoniya am)ila Da!l. 



Panopea generosa (iould. 



Pecten caurinns Gould. 



Pecten hastatus Sowerljy. 



Pecten liastatus var. heririus Gould. 



Pecten hastatus var. hindsii Carpenter. 



*Pecten jordani Arnold. 



*Pecten stearnsii Dall. 



Phacoides acutilineatun Conrad. 



PhacoidcK ealifornicus Conrad. 



Pholadidea jienita Conrad. 



Protocardia ceiitililosa Carpenter. 



8olen sicarius Gould. 



*Thracia trapezoides Conrad. 



Thyasira goiddii Philippi. 



Thyasira bisecta Conrad. 



Venericardia l>arbarensis .Stearns. 



Venericartlia ventricosa ( iould. 



Venus (Chione) simillima Sowerby. 



(H.STEIiOPODA. 



.\cm;ea insessa Hind.s. 

 Aniphissa corrugata Reeve. 

 Bela fidicula Gould. 

 Bittium asperum Gabb. 

 Calliostoma canaliculatuni ilartyn. 

 Calliostonia tricolor Gabb. 

 Cerithidea californica Haldemann. 

 Chlorostonia brunneurn Philippi. 

 Chlorostonia montereyi Kiener. 

 Chrysodonius up. indet. 

 Chrysodonuis rectirostris Cai'pentcr. 

 Chrysodomus tabulatus Baird. 

 Clathurella conradiana Gabl). 

 Columbella gausapata Gould. 

 Columbella gausapata var. carinata Hinds. 



<;.\STEROPODA — contniued. 



Conus ealifornicus Hinds. 



Cryptochiton stelleri Middendorf. 



*DriHia merrianii Arnold. 



Drillia torosa Carpenter. 



Fusus barbarensis Trask. 



Hipponyx anti(|uatus I.inne. 



Litorina planaxis ( NuUall ) Philippi. 



Mangilia sculpturata Dall. 



Nassa californiana Conrad. 



Na.«sa fossata Gould. 



Nassa mendica Gould. 



Nassa mendica var. ccjoperi Forbes. 



Nassa perpinguis Hinds. 



Natica clausa Broderip and Sowerby. 



Neverita recluziana Petit. 



Ocinebra interfossa Carpenter. 



Olivella l>iplicata Sowerby. 



Olivella intorta Carpenter. 



Olivella jiedroana Conrad. 



* Pleurotoma Viartschi Arnold. 

 *Pleurotonia dalli Arnolil. 

 Pleurotoma perversa Gablj. 



* Pleurotoma renaudi .\rnold. 



* Pleurotoma smithi .\rnold. 

 Priene oregonensis Redfield. 

 Puncturella cuciillata (xoulil. 

 Puncturella galeata Gould. 

 Scala indianorum Carpenter. 

 Solariella cidaris \. Adams. 

 Solariella peramabilis Carpenter. 

 *Taranis strongi Arnold. 

 Terebra simplex Carpenter. 

 Thalotia caffea Gabb. 

 Tornatina eximia Baird. 

 Trophon gracilis Perry. 

 Trophon pacificus Dall. 

 Trophon stuarti Suiitli. 



* Trophon orpheus var. prfecursor .\rnold. 

 Trophon tenuisculpta Carpenter. 

 Turritella cooperi Carpenter. 

 *Turritella jewetti Carpenter. 



PLEISTOCENE. 



The insuine Pliocene and Pleistocene deposits of Ciilifornia are intimately asso- 

 ciated, and at many places grade into each other with no perceptible physical break 

 between them. At others, however, an unconformity exists between the two, and 

 in some localities the Pleistocene itself may be separated into two divisions, with a 

 more or less distinct line of demarcation between them. Such a condition as that 

 last mentioned is found in the vicinity of !San Pedro, Los Angeles County, where 



