IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 141 



1956 Rugotruncana tilevi Bronnimann & Brown : 547, pi. 22, figs. 1-3. 

 1956 Rugotruncana ellisi Bronnimann & Brown : 547, pi. 22, figs. 7-9. 

 i960 Globotruncana (Rugotruncana) tilevi (Bronnimann & Brown) ; Pessagno : 102, pi. 5, 



fig. 10. 

 1962 Globotruncana (Rugotruncana) subcircumnodifer (Gandolfi) Berggren : 67-69, pi. 10, 



figs. 4«-c. 



Remarks. Gandolfi (1955) considered Globigerina circumnodifer Finlay to belong 

 to Rugoglobigerina which he regarded as a subgenus of Globotruncana Cushman, and 

 described the present form as a new subspecies. 



Berggren (1962) stated that examination of the holotypes of G. (R) circumnodifer 

 Gandolfi, G. (R) pennyi subpennyi Gandolfi, R. tilevi Bronnimann & Brown and R. 

 ellisi Bronnimann & Brown proved them all to be junior synonyms of G. (R) circwm- 

 nodifer subcircumnodifer Gandolfi. He proposed the elevation of this subspecies to 

 specific rank, naming it Globotruncana {Rugotruncana) subcircumnodifer Gandolfi as 

 Finlay's form appears to be a true Rugoglobigerina. However, as Rugotruncana is a 

 junior synonym of Globotruncana Cushman, as mentioned above, the name of the 

 species is here considered as G. subcircumnodifer Gandolfi. 



Hypotype. P. 45560. 



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

 section. 



Stratigraphical range. Gandolfi (1955) recorded this species from the Colon 

 shale of northeastern Colombia, where he considered its range as Campanian (in fact 

 it is most probably Maestrichtian as explained on p. 133). 



Bronnimann & Brown described their R. ellisi and R. tilevi, from the Campanian- 

 Maestrichtian of Texas and Arkansas, and from the Upper Maestrichtian of Habana, 

 Cuba, respectively. 



Globotruncana subcircumnodifer was also recorded from the Lower Maestrichtian 

 of Puerto Rico (Pessagno i960), and from the Lower Maestrichtian of Scandinavia 

 and New Jersey (Berggren 1962). 



In the Esna-Idfu region, G. subcircumnodifer is recorded as a common form in the 

 Middle Maestrichtian G. gansseri Zone, fading out gradually upwards in the section 

 to occur as a rare scattered form in the Upper Maestrichtian G. esnehensis Zone, 

 where it dies out completely. 



Globotruncana tricarinata colombiana Gandolfi 



1955 Globotruncana tricarinata colombiana Gandolfi : 20-22, pi. 1, figs. 3a— 4c ; ? text-figs. 5 

 (ia-2c), 6 (4a, b). 



Remarks. Globotruncana tricarinata colombiana was first described by Gandolfi 

 (1955) from the Manaure and Colon shale formations of northeastern Colombia. It 

 is believed to have evolved from G. tricarinata tricarinata (Quereau) as mentioned by 

 Gandolfi, who also suggested that it evolved into the form he described as " G. tri- 

 carinata colombiana? ". However, the latter is more closely related to the G. forni- 



