Vol. 4] Weaver. — Palaeontology of the Martinez Group. 



111 



46 Morio tubereulat us Gabb 



47 Natica, sp 



48 Neptunea mucronata Gabb X 



49 Perissolax tricarnatus, n. sp X 



50 Perissolax blakei Gabb 



51 Siphonalia lineata Stanton X 



52 Architect onica tuberculoid, a. sp 



53 Strepsidura pachecoensis Stanton 



54 Tritonium impression, n. sp 



55 Tritonium eocenieum, n. sp 



56 Tritonium pulchrum, n. sp 



57 Turbinella crassitesta Gabb X 



58 Turritella infragranulata Gabb 



59 Turritella pachecoensis Stanton 



60 Turritella conica, n. sp 



61 Turris, sp. indet 



62 Urosyca caudata Gabb X 



63 Urosyca robusta, n. sp X 



64 Xenophora zitteli, n. sp X 



65 Cancer, (?) sp 



66 Crustacean remains, maeruran 



67 Serpula X 



X 

 X 

 X 

 X 

 X 

 X 



X 

 X 

 X 

 X 

 X 



X 

 X 



CORRELATION. 



Because of the somewhat divergent views held by various 

 writers in regard to the correlation of the different divisions of 

 the Eocene in other parts of the world, and owing to the fact that 

 a large majority of the species occurring in the Pacific Coast 

 Eocene are not represented elsewhere, it becomes extremely diffi- 

 cult to make a correlation of the Eocene of the West Coast with 

 other sections. In 1898 Dr. W. H. Dall* drew up a correlation 

 table of the American and European Eocene. In this paper he 

 represents the combined Eocene of the Pacific Coast as the 

 equivalent of the Midway stage of the Atlantic and Gulf States, 

 and of the Cernaysian of Europe. Thus, according to his views, 

 the Martinez and Tejon groups, taken together, form the lower 

 Eocene. Since in this case no use can be made of species, as 



*18th Ann. Kept. U. S. (ieol. Survey, Pt. 2, pp. 327-348, 1898. 



