26 TERTIARY AND QUATERNARY PECTENS OF CALIFORNIA. 



The greater part of the San Pablo should, without question, he placed in the 

 Miot-ene, while the major portion of the Puritsima is undoubtedly Pliocene. In 

 accordance with these facts each formation has been arbitrarily placed in that epoch 

 with which it appears to be the more closely allied. 



LOCALITIES. 



Crescent City, Del Norte County. 



Eel River, Humlioldt County. 



Toniales Bay, ]Marin County. 



Halfmoon Bay to Pesoadero Creek, vicinity of La Honda, Alpine district, and ridge west of Portola 



Valley, San Mateo County. 

 Near mouth of Stev'ens Creek, Santa Clara County. 

 West branch of Soquel Creek and Scott Valley, Santa Cruz County. 

 Cholame Valley, Lewis Creek, and Priest Valley, Monterey County. 

 Vicinity of Coalinga, Kreyenhagens, and the Kettleman Hills, Fresno County. 

 Cosmalia, Santa Barbara County. 

 Temescal Canyon in Santa Monica Moinitains, Third street and Broadway tunnels in Los Angeles, and 



San Fernanilo tunnel, Lus Angeles County. 

 Olinda, Orange County. 

 Cerros Island, off the coast of Lower California, Mexico. 



The formations exposed at the following localities probal)ly represent the upper 

 part of the Purisima and the lower part of the Merced, and correspond to Dall's San 

 Diego formation: 



Santa Barbara and Rincon asphalt mine, Santa Barbara County; Piru Creek and Eureka Canyon, 

 Ventura County; Santa Monica Canyon and San Pedro, Los Angeles County; San ,Iuan 

 Capistrano, Orange County; San Diego and Pacific Beach, San Diego County. 



FAUNA. 



The fauna of the Purisima in central California contains a few .species which 

 extend into the Vaqueros (lower Miocene), many more which are common to it and 

 to the San Pablo (upper Miocene), and a large number which are found in the 

 Merced above it or are living at the present time. A number of the species com- 

 mon to the San Pablo and the Purisima are not found in the Merced or later, while 

 a large number of the species found in both the Merced and the Purisima do not 

 extend into the San Pablo, so far as known. Quite a number of the forms found in 

 •the Purisima are peculiar to this formation. Of the total Purisima fauna, about 30 

 per cent are believed to be extinct. 



The fauna of the "Wildcat" series of Humboldt County, as determined liy 

 Merriam and given by Lawson," indicates the probable contemporaneity of at least a 

 part of this series with the Purisima. The lower part of the San Diego formation 

 probably represents the middle and upper portions of the Purisima. 



Pecten fauna. — The Pecten fauna of the Purisima and supposed equivalent for- 

 mations is as follows: P. ashleyi, P. auhuryi, P. hartschi., P. hcNiLs, P. hellilamel- 

 hifiis, P. caiirinus, P. cerrosetrsis, P. coaUngaensis, P. cooperi, P.d/'Ueri, P. estrellanus 

 var. catalin3e, P. {Hinnites) giganteits, P. hastahis and its varieties /tericius, hindsii, 

 iiavarchus, strategus, P. healeyi., P. hempkilU, P. islandicus, P. jordani, P. latiati- 



<i Lawson, X. C, Bull. Dept. Geol., Univ. Cal., vol. i, 1894, No. 8, pp. 260-261. 



