1915] 



Clark: Fauna of the San Pablo Group 



427 



RELATION OF SAN PABLO FAUNA TO RECENT FAUNA 



A noticeable feature of the San Pablo fauna is the close genetic 

 relationship of many of its extinct species to the Recent fauna of the 

 Pacific Coast. Every such species is related to a form now living in 

 the same geographical province as that in which the fauna of the 

 San Pablo would be found if it were living at the present day. Below 

 are lists of the extinct species and the Recent species to which they 

 are obviously closely related. 



Extinct 

 Acila eonradi Meek. 

 Amiantis dalli, n. sp. 

 Chione diabloensis, n. sp. 

 Chione pabloensis, n. sp. 

 Macoma andersoni, n. sp. 

 Macoma diabloensis, n. sp. 

 Tellina englishi, n. sp. 

 Tivela gabbi, n. sp. 

 Tivela diabloensis, n. sp. 

 Astralium raymondi, n. sp. 

 Columbella (Astyris) kirkensis, 

 n. sp. 



Calliostoma splendens var. dia- 

 bloensis, n. var. 

 Leptothyra pabloensis, n. sp. 

 Littorina pittsburgensis, n. sp. 

 Murex (Ocinebra) dalli, n. sp. 

 Murex (Ocinebra) selbyensis, n. sp. 

 Natica (Euspira) kirkensis. 

 Natica (Neverita) pabloensis. 

 Tegula (Chlorostoma) nashi, n. sp. 



Eecent 

 Acila castrensis Hinds 

 Amiantis callosa Conrad. 

 Chione simillima Sowerby. 

 Chione simillima Sowerby. 

 Macoma indentata Cpr. 

 Macoma nasuta Conrad. 

 Tellina idaea Dall. 

 Tivela stultorum Mawe. 

 Tivela stultorum Mawe. 

 Astralium undosa Wood. 

 Columbella (Astyris) gausapata 

 Gould. 



Calliostoma splendens Carpenter. 

 Leptothyra carpenteriana 



Pillsbury 

 Littorina planaxis Nuttall. 

 Murex (Ocinebra lurida) 



Middendorf. 

 Murex (Ocinebra lurida) 



Middendorf. 

 Natica (Euspira) lewisi Gabb. 

 Natica (Neverita) recluziana Petit. 

 Tegula (Chlorostoma) aureatinc- 

 tum Forbes. 



TEMPERATURE CONDITIONS OF SAN PABLO SEA 



We may judge of the temperature of the waters of the San Pablo 

 sea from the present geographical range of the Recent species in its 

 fauna. With this as a criterion, the waters of that sea were of about 

 the same temperature as the waters of the present coast between Point 

 Conception and Santa Barbara. According to Philip P. Carpenter, 24 

 the temperature of these waters is about the same as those of the 



24"Mollusca of the West Coast of North America," Brit. Assoc. Rep., p. 167, 

 1856. 



