THE AMERICAN SPECIES OF ORTHOPHRAGMINA AND LEPIDOCYCLINA. 



By Joseph A. Cushman. 



INTRODUCTION. 



Orbitoid Foraminifera, on account of their 

 short stratigraphic range, have proved to be 

 excellent horizon markers, and, because of 

 their wide geographic distribution, they are 

 valuable in correlation. The genus Orhitoides, 

 as now restricted, is found exclusively in de- 

 posits of Cretaceous age; OrtliopJiragmina ap- 

 pears to be confined to the Eocene ; but Lepido- 

 cyclina ranges through the upper Eocene and 

 Oligocene. 



In the present paper are described all the 

 known American species of Orthopliragmina 

 and Lepidocyclina. The species are listed be- 

 low in groups according to the geologic forma- 

 tions in which they are found. The relative 

 ages of the formations are shown in the ac- 

 companying correlation table, which is copied 

 from a paper by T. W. Vaughan.^ As stated 

 in the footnote to the table, I am not in accord 

 with DouviUe regarding the age of the lime- 

 stone on Haut Chagres and near David, Pan- 

 ama, but regard it as Eocene because it con- 

 tams two species of OHliophragmina,. How- 

 ever, two of the three species of Lepidocyclina 

 foimd near David {L. panamensis and L. du- 

 plicata) occur also near Tonosi, Panama, asso- 

 ciated with fossils characteristic of the middle 

 Oligocene, the age of the lower part of the 

 Culebra formation; and L. chaperi, described 

 originally from Haut Chagres, occurs in the 

 Culebra formation at a higher horizon. 

 American species of Orthophragmina and Lepidocyclina. 



EOCENE. 



Ocala limestone : 



OrthophragmiQa fiintensis Cushman. 

 georgiana Cushman. 

 mariannensis Cushman. 

 mariannensis var. papillata Cushman. 

 vaughani Cushman. 

 americana Cushman. 



I The biologic character and geologic correlation of the sedimentary 

 formations of Panama in their relation to the geologic history of Centraj 

 America and the West Indies: U. S. Nat. Mus. Bull. 103, table facing p. 

 595, 1919. 



Ocala limestone — Continued. 



Lepidocyclina georgiana Cushman, n. sp. 

 fragilis Cushman, n. sp. 

 pseudocarinata Cushman, n. sp. 

 cookei Cushman, n. sp. 

 attenuata Cushman, n. sp. 

 fioridana Cushman, n. sp. 

 pseudomarginata Cushman, n. sp. 

 ocalana Cushman, n. sp. 

 ocalana var. subdecorata Cushman, n. var. 

 hilli Cushman, n. sp.? 

 Jackson formation : 



Lepidocyclina mortoni Cushman, n. sp. 

 St. Bartholomew limestone: 



Orthophragmina marginata Cushman. 



antillea Cushman. 

 Lepidocyclina antillea Cushman. 

 Brito formation (Nicaragua): 



Orthophragmina hayesi Cushman, n. sp. 

 flintensis Cushman. 

 georgiana Cushman. 

 David, Panama: 



Orthophragmina minima Cushman. 



antillea Cushman. 

 Lepidocyclina macdonaldi Cushman. 

 panamensis Cushman. 

 duplicata Cushman. 

 Haut Chagres, Panama: 



Lepidocyclina chaperi Lemoine and R. Douvill4. 

 Cuba: 



Orthophragmina cubensis Cushman. 

 pustulata Cushman. 

 crassa Cushman. 

 sculpturata Cushman. 

 subtaramellei Cushman. 

 Lepidocyclina perundosa Cushman. 

 subraulinii Cushman. 

 California: 



Orthophragmina clarki Cushman, n. sp. 



OLIGOCENE. 



Marianna limestone : 



Lepidocyclina mantelli (Morton). 

 Byram calcareous marl: 



Lepidocyclina supera (Conrad). 

 Chattahoochee formation : 



Lepidocyclina chattahoocheensis Cushman, n. sp. 

 Antigua formation : 



Lepidocyclina undulata Cushman. 

 undosa Cushman. 

 gigas Cushman. 

 favosa Cushman. 

 canellei var. yumagunensis Cushman. 



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