— 6 — . 



given by Carpenter, in the " West Coast Mollusca," were the chief 

 sources of information on the subject at the time, and to find a grain 

 of information required hours of search, often with negative results. 

 The present bibliography, besides condensing the subject into system, 

 adds very much from many sources, and is believed to be a nearly 

 complete catalogue of the original authors and their works. 



Of the authors treating only of fossils of the formations older than 

 Miocene there are but few. and little mention has been necessary, as 

 they are fully referred to in the " Palaeontology of California." For the 

 same reason, most of the fossils of those formations being described as 

 new by Meek or Gabb, it is not necessary to repeat the catalogues of 

 them given in the Report of the Mining Bureau of 1887. 



As to the new species, described since that date by Dr. C. A. White 

 in publications of the United States Geological Survey, they are also 

 easily accessible, and do not need further cataloguing. 



Some of the different groups of fossils probably indicate that they 

 lived at different depths before the upheaval of the land, but that does 

 not explain the facts of distribution of species now found on seashores 

 in other regions, but extinct here. 



The fresh-water deposits usually found with lignite beds in strata of 

 various ages are of special interest, on account of their indications of 

 the existence of dry land, as well as being proofs that the lignite is of 

 little extent or value. 



Their uplifted position also exhibits the effect of volcanic forces, and 

 shows in arid regions what changes in climate have occurred since the 

 period when abundant rainfall caused lakes to exist where little or no 

 water now remains. 



BIBLIOGRAPHY OF FOSSIL MOLLUSCA. 



ADAMS, CHARLES B., Professor, Amherst College. Catalogue of 

 Panama Shells, from Annals of the N. Y. Lyceum of Nat. Hist., vol. 

 V, 1852 ; also separately. Full notes and descriptions; no figures. 

 Out of nearly five hundred species, over one hundred were new; but 

 very few of them extend to California, though many of the species are 

 found living or fossil farther north. (Catal. Panama Shells.) 



ADAMS, HENRY and ARTHUR. Various articles published in 

 the Proceedings of the Zoological Society of London, 1835 to 1876. 

 (Proc. Zool. Soc. Lond.) 



The Genera of Recent Mollusca, 2 vols., 8vo, and 138 plates. Lon- 

 don, 1853-83. This fine systematic work contains figures and descrip- 

 tions of several West Coast mollusca. (H. and A. Adams' Genera.) 



ANTHONY, JOHN G. Boston Journal of Nat. His., vol. Ill, 1840. 



