40 



University of California Publications in Geology [Vol. 10 



collecting a fauna of approximately 160 species was obtained. The 

 material, which is in a splendid state of preservation, was entrusted 

 to the University of California for study. 



It is with pleasure that the writer acknowledges his indebtedness 

 to Mr. Gilbert for his generosity in providing the abundant material 

 for study, and to Professor J. C. Merriam and Dr. B. L. Clark for 

 co-operation and valuable assistance during the progress of the work. 

 This opportunity is also taken to thank Mrs. Ida Oldroyd for consul- 

 tation, Dr. Paul Bartsch, Dr. Ralph Arnold and Mr. Homer Hamlin for 

 information which has aided materially in the course of the study, 

 and Professor W. J. Raymond for access to his splendid molluscan 

 collection. 



Occurrence 



The fauna upon which the following report is based was obtained 

 from a bluish gray clay exposed by excavation for a building site on 

 Fourth Street between Hill Street and Broadway, near the center of 

 the city of Los Angeles. Shells were first found at thirty-four feet 

 from the surface. A communication from Mr. Gilbert states that the 

 clays seemed to dip a few degrees toward the northwest. 



In the geologic map of the Los Angeles oil fields accompanying 

 the text of Bulletin 309 of the United States Geological Survey, the 

 locality under consideration is included in the Fernando formation. 

 It is also stated in this bulletin 1 that marine Pleistocene deposits 

 overlie the true Fernando in the region of the oil belt and farther 

 south, especially on the top of the ridge on which the Normal School 

 is situated. As the locality described is now inaccessible, question 

 arises whether the fossils under discussion were obtained from these 

 terrace deposits or from the true Fernando. From a consideration 

 of various phases of the fauna to be discussed later, no hesitation is 

 felt in assigning it to the latter formation. 



Previous Knowledge op Related Occurrences 

 Fossils have been known from various localities in Los Angeles 

 since the opening of the oil fields in and around the city. In Bulletin 

 11 of the California State Mining Bureau, 1896, W. L. Watts 2 gives 

 a list of 34 species obtained from oil wells and from the site of the 

 State Normal School on Fifth Street, which present a faunal facies 

 not different from those obtained from the Fourth Street locality. In 



1 Arnold, E., Bull. IT. S. Geol. Surv., no. 309, p. 153, 1907. 



2 Watts, W. L., Bull. Calif. State Min. Bureau, no. 11, pp. 79-81, 1896. 



