Mesozoic and CcBnozoic Geology and Palaeontology. 149 



grandis, now Dispotosa grandis, Fissurella redimicula, Ostrea com- 

 pressirostra, Pecten jeffersonius, P. madisonius, P. cUntomus, P. sep- 

 tenari/us., Plicatitla marginata; and from strata now referred to the 

 Pliocene of Maryland, Area arata, A. centenaria^ A. incile, Pectun- 

 ciilus subovatus, Nucula concentrica., iV, laevis, Venericardia granu- 

 lata, now Cardita granulata, Crassafella unditlata, Isocardiafraterna, 

 Tellina aeqnisti iata, Lucina anodonta, L. contracta, L. crihraria, L. 

 subobliqua, Venus deformis^ Astarte undulata, A. vicina, Amphi- 

 desma sitbovatum, Corbiila cimeata, C. inaequalis, Panopcea reflexa^ 

 Serpula granifera, and Dentalium attenuatum. 



In 1825, Dr. Richard Harhxn* described, from Bigbone Lick, Ken- 

 tuck}', Cervus americanus, Bos bombifrons, now Ovibos bornbifrons, B. 

 lati/rons, now Bison latifrons ; from a cave in Greenbriar county, 

 Virginia, Ifegalonyx jeffersoni.^ and from Skidaway Island, Georgia, 

 Megatherium cuvieri. 



In 1828, Dr, J. E. Deka3'f described, from the Post-pliocene at New 

 Madrid, on the Mississippi river, Bos i^allasi. 



In 1829, Dr. Morton']; arranged, from the notes of Lardner Vanux;em, 

 some geological observations on the Tertiary and Alluvial formations 

 of the Atlantic coast of the United States, showing their great extent 

 and inclination from Nantucket and Martha's Vineyard, on the coast 

 of New England, to the Mississippi river. The modern alluvial was 

 divided into vegetable mould and river alluvium; the ancient alluvial 

 into white siliceous sand and red earth; the Tertiary formation into 

 beds of limestone, buhrstone, sand and clay. He described, from 

 strata now regarded as Pliocene. Crepiduld costata. 



In 1830, Mr. Timothy A. Conrad§ showed that Tertiary deposits 

 occupy all that part of Maryland south of an irregular line, running 

 from the vicinity of Baltimore to Washington Citv, between the 

 Potomac river and Chesapeake bay, though most of the surface is 

 covered with a diluvial deposit of sand and gravel; and from the pres- 

 ence of Turritella mortoni, Cucullcea gigantea, and Venericardia 

 planicosta, he regarded the deposits in the vicinit}' of Fort Washing- 

 ton as contemporaneous with the London clay of England, which now 

 constitutes part of the Eocene of Europe, This was the first announce- 

 ment of the existence of strata, of this age, in America, 



* Fauna Americana. 

 i Am. Lye. Nat. Hist., N. Y., vol, ii. 

 t Jour. Acad. Nat. Sci,, vol. vi., pt. 1. 

 ? Jour. Acad, Nat, Sci., vol, vi., pt. 2. 



