1920] 



Stock: An Early Tertiary Vertebrate Fauna 



275 



appears to be some faunal evidence, however, warranting the sup- 

 position that the time interval indicated by the ditference is such as 

 to be not fully expressed in terms of continuous deposition of a single 

 series of beds. Obviously, if the vertebrates are found to pertain to 

 deposits not included within basal strata of the Monterey Series, the 

 latter group must then be assigned to an age later than uppermost 

 Oligocene or lowermost Miocene. 



Table Giving Position of Tecuja Fauna with Reference to 

 Miocene and Oligocene Faunas 



Geological 

 Periods 



Pacific Coast Marine Province 



Great Basin 

 Province 



Great Plains 

 Province 



Formations 



Vertebrate 

 fauna 



Invertebrate 

 fauna 



Miocene 



San Pablo 

 Monterey 

 Vaqueros 



Merychippus 

 zone 



Turritella 



oeoyana 

 Turritella 

 inezana 



Barstow 



Mascall and Vir- 

 gin Valley 



Santa Fe 



Deep River 



Lower Harrison 

 Lower Rosebud 



Oligocene 



San Lorenzo 



Tecuja or 

 Sespe? 



Agasoma 

 gravidum 



John Day 



Brule 

 Chadron 



Two marine invertebrate assemblages, namely the Turritella 

 oeoyana fauna and the Turritella inezana fauna, are associated with 

 the Monterey Series in California. The invertebrate remains known 

 from strata above the red beds with mammalian fossils in the Tecuja 

 Canon area are presumably indicative of the T. inezana fauna. Should 

 the latter zone be actually represented in this region, the vertebrates, 

 found in sediments which apparently exhibit no discontinuity with 

 the overlying marine deposits, may be regarded as yielding evidence 

 in support of a current belief among investigators that the Vaqueros 

 is both a strati graphic and a faunal unit distinct from the Monterey.® 



The relation of the red beds containing the vertebrate remains in 

 the Tecuja Canon region to the overlying Monterey marine deposits, 

 presumably with a Vaqueros fauna, is similar to that which the Sespe 

 formation at the type locality on Sespe Creek, Ventura County, Cali- 



Loel, W. r., The Vaqueros formation in California, Abstract in Proc. 8th 

 Ann. meeting of Pacific Coast Branch, Paleontological Society, 1917, Bull. Geol. 

 Soc. Amer., vol. 29, p. 165, 1918. 



