182 bulletin: museum of comparative zoology. 



same relative position above folded terrigenous formations as in Bar- 

 bados and Jamaica. These beds, variously called San Fernando and 

 Naparima by Guppy, contain the characteristic Glohigerinae, Orhitoides, 

 and NummulincB of the Cambridge and Montpelier beds of Jamaica, and 

 in Guppy's latest papers are referred by him to the Eocene/ although 

 for many years he placed them in the Miocene. The position of the 

 white Eadiolarian marls above a great series of clays and sandstones 

 resembling the Scotland rocks of Barbados (Richmond beds of Jamaica) 

 has been later confirmed by the observations of Harrison.^ 



Extensive deposits of Eadiolarian earths occur nowhere, so far as we 

 are aware, adjacent to the eastern side of the American continent. The 

 occurrence of these apparently synchronous oceanic beds in the widely 

 separated West Indian localities of the Antilles, Trinidad, and Barbados, 

 indicate deep water conditions in each of the regions. 



The Vicksburg-Jackson formation of the Gulf States Tertiary is in 

 my opinion synchronous with that of the oceanic beds of the Montpelier 

 epoch of the Antillean region, and are probably the northern shallow 

 attenuation of the oceanic beds of the West Indies. They are charac- 

 terized by the species Orhitoides manteUi, and in Florida JVummuliiice 

 also occur. Although composed largely of oceanic material they are 

 shallower beds than the Antillean formations. The visible effect of 

 the Antillean subsidence reflected in the sediments of the Tertiaries of our 

 southern coast was to change their character from the non-calcareous 

 nature observable in the Claiborne to more calcareous deposits of the 

 Jackson and Vicksburg beds. In Alabama and Mississippi the Vicks- 

 burg beds, with the overlying Jackson, are white limestones, the 

 combined thickness aggregating about 500 feet. In Florida the 

 Vicksburg beds outcrop in the northern portion of the State. Be- 

 neath the Pliocene coating of Southern Florida the Vicksburg beds, 

 as exposed by well drillings, have a thickness of 200 feet, and contain 

 the characteristic Orhitoides and Nummidinct. Their microscopic nature 

 has not been investigated. These beds are characterized by the three 

 genera of Foraminifera, Orhitoides mantelli (the Orhitoides limestone *), 

 Nurmmdince,'^ and MilolidcE^^ which are so abundant in the lower part of 

 the Montpelier of Jamaica and Southern Mexico. 



1 Quart. Jour. Geol. Soc. London, 1892, Vol. XLVIII. pp. 5^-524. 



2 Quart. Jour. Geol. Soc. London, 1802, Vol. XLVIII. p. 218. 

 8 Dall, Bull. 84, U. S. Geological Survey, page 101. 



. * Ileilprin, cited by Dall, Bull. 84, U. S. Geological Survey, pages 103, 104. 

 c Ibid., p. 104. 



