THE SMALLEE FOSSIL FOEAMINIFEEA OF THE 

 PANAMA CANAL ZONE. 



By Joseph Augustine Cushman, 



Of the United States Geological Survey. 



INTRODUCTION. 



The collection of fossil foraminifera included in this report were 

 sent to the writer by the United States Geological Survey. It con- 

 sists almost entirely of material collected by Messrs. D. F. Mac- 

 Donald and T. Wayland Vaughan in 1911, to whom I am indebted 

 for data as to the geological correlation. The names applied to the 

 geologic formations are those used in MacDonald's " Sedimentary 

 formations of the Panama Canal Zone, with special reference to the 

 stratigraphic relations of the fossiliferous beds," which appears in 

 the latter part of this volume. Where former correlation has seemed 

 not to apply to the foraminifera, especially those of three stations, 

 6033<?, 6035, and 6036a, discussion of the data obtained from the 

 foraminifera is given in detail later. 



The orbitoids and nummulites are both well represented in the 

 collection, but as these require special study in connection with those 

 of the Coastal Plain and of the West Indian region it seems ad- 

 visable to treat them in a separate paper which immediately followsi 

 the present one. 



The following data are given for only the stations from which 

 foraminifera were obtained and which are recorded in this paper. 



LIST OF MATERIAL. 



U.S.G.S. station 6009. — Oligocene — Gulebra formation (upper part). 

 From section in Canal cut 600 feet south of Miraflores Locks. 

 Dark, soft, fairly well laminated clay rock. 

 Few foraminifera and rather poorly preserved. 

 6010. — Oligocene — Gulebra formation (lower part). 



From section — Pedro Miguel Locks to Paraiso Bridge. 

 Dark, well laminated, very soft, carbonaceous clay rocks. 

 Foraminifera in fairly good numbers and a rather varied assort- 

 ment; mostly stained black, except certain of the Miliolidae, 

 which still keep their calcareous tests more or less in their 

 original condition. 



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