TERTIARY LARGER FORAMINIFERA OF VENEZUELA 



By DONALD WINCHESTER GRAVELL 



Gulf Production Co., Houston, Texas 



(With Six Plates) 



INTRODUCTION 



This paper presents the results of a study of larger Tertiary f orami- 

 nifera of Venezuela, collected in 1925-26 by Dr. H. G. Kugler and 

 Dr. L. Vonderschmitt ; in 1927 by Drs. P. Leuzinger, P. A. Messmann, 

 and A. Senn ; and in 1928 by Mr. M. N. Bramlette. These were sent 

 to Dr. T. Wayland Vaughan, Director of Scripps Institution of 

 Oceanography, University of California, La Jolla, California, who 

 permitted me to study the material. 



The great portion of the material in these collections is indurated, 

 and therefore the specimens had to be studied mostly in thin sections, 

 of which I prepared nearly 300. For these reasons specific determi- 

 nations of many specimens have not been made. It is possible that 

 additional material from other localities may yield specimens which 

 may be separated from the matrix, and the study of them in thin 

 sections may make possible the determination of part of the specimens 

 in this collection. Among the genera recognized were Acervulina, 

 Archaias, Carpentcria, Cameriiia, Heterostcgiiia, Operculina, and cer- 

 tain species of Discocyclina and Lepidocyclina. Some specimens of 

 the last two genera were free from the matrix. 



While at Scripps Institution of Oceanography, I was able to com- 

 pare this Venezuelan collection with the valuable collection belonging 

 to that Institution, and also with a part of the United States National 

 Museum collection which Dr. Vaughan was using at the time. These 

 collections contain authentically identified specimens of most of the 

 described American species of larger foraminifera. 



Types of the new species and a complete set of the other material 

 will be deposited in the United States National Museum ; and para- 

 types together with other material will be divided between the Natur- 

 historisches Museum in Basel, Switzerland, and the Scripps Institution 

 of Oceanography. 



The work on this paper was done under the supervision of Dr. T. 

 Wayland Vaughan, to whom I am greatly indebted for many helpful 



Smithsonian Miscellaneous Collections, Vol. 89, No. 11 



