IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 125 



was shown to have two closely spaced keels. He also noticed that in the specimens 

 he studied from the Maestrichtian of southeastern Turkey, there were forms with 

 double and single keels. He also considered G. rosetta rosetta (Carsey) as a junior 

 synonym of the present species in spite of its priority. 



Bronnimann & Brown (1956) confirmed Tilev's earlier observation stating that 

 " In an examination of the holotype of Git. cretacea Cushman, two keels, very close 

 together, were observed in all chambers of the last whorl ". These two authors also 

 considered the present species to be intermediate between G. lapparenti Brotzen and 

 G. rosetta (Carsey). 



Banner & Blow (i960) proved Globigerina cretacea d'Orbigny, 1840, to be a true 

 Globotruncana, and thus changed its name to Globotruncana cretacea (d'Orbigny) 

 whereby Globotruncana cretacea Cushman 1938, became a junior homonym, which 

 they renamed Globotruncana mariei nom. no v. 



Globotruncana mariei is distinguished by its medium-sized, planoconvex to 

 unequally biconvex test, its chambers which increase rapidly in size in the last whorl, 

 its very closely spaced keels, and strongly overlapping chambers on the ventral side, 

 and by its smooth test and somewhat rougher keels. 



Contrary to Tilev's observation (1951, 1952), G. marei is quite distinct from G. 

 rosetta rosetta (Carsey), although Bronnimann & Brown (1956) stated that it seems to 

 be an incipient form of G. rosetta. 



Nakkady (1951a) described as G. cretacea Cushman from Duwi, Mellaha, Durba 

 and Danilli sections, Egypt, forms which include G. stuarti stuartiformis Dalbiez, 

 G. aegyptiaca aegyptiaca Nakkady and G. gagnebini Tilev, as examination of his 

 specimens (B.M. N.H., P. 41782) has revealed. 



Nakkady also figured as G. pseudocretacea n.sp., a form which most probably 

 belongs to G. gagnebini Tilev, or is transitional between it and G. ventricosa White, 

 as examination of his type specimens (B.M.N.H., P. 41783-84) has revealed. How- 

 ever, Berggren (1962) wrongly considered G. pseudocretacea to be a nomen nudum 

 and stated that Nakkady 's specimens were related to G. rosetta rosetta (Carsey). 



Hypotype. P.45548. 



Horizon and locality. Hypotype from sample No. 18, W. El-Sharawna 

 section. 



Stratigraphical range. Globotruncana mariei was first described from the 

 Upper Campanian, Selma chalk of Tennessee. Most records show that it ranges 

 throughout the Upper Campanian and the Maestrichtian. 



In the Esna-Idfu region, G. mariei occurs as a common form throughout the 

 Maestrichtian, G. fornicata, G. gansseri and G. esnehensis Zones, being most common 

 at the base and fading out gradually upwards in the section. 



Globotruncana orientalis sp. nov. 

 (PL 12, figs. t\a-d) 



Diagnosis. A Globotruncana with broadly arched dorsal side and almost flat 

 ventral one, two closely spaced keels in early part, reduced to one in the last chambers ; 



