IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 93 



(Gandolfi 1955) ; the Lower and Upper Maestrichtian of the Gamsa Basin, Austria 

 (Wicher 1956) ; the Lower-Upper Maestrichtian boundary, Cr 4 -Mb, at Leon, 

 Belgium (Hofker 1956a) ; the Lower and Upper Maestrichtian of the Atlantic 

 Coastal Plain (Olsson i960) ; the Maestrichtian of the Prahova Basin, Romania 

 (Vinogradov i960) ; and from the type Maestrichtian of Holland (Hofker 1960a, 

 1962a). 



In the Esna-Idfu region, G. contusa contusa appears in the basal part of the 

 G. gansseri Zone. It gradually increases in numbers upwards in the section, to 

 flood this zone, and then fades out gradually, dying out completely in the overlying 

 G. esnehensis Zone. No typical representatives of this subspecies were recorded in 

 the Lower Maestrichtian G. fornicata Zone, which is flooded with transitional stages 

 between the G. fornicata and G. contusa groups (e.g. G. contusa witwickae) ; while only 

 rare forms were recorded throughout the G. esnehensis Zone. 



All reliable references show that G. contusa contusa ranges throughout the Middle 

 and Upper Maestrichtian. All records of this subspecies from rocks older than the 

 Middle Maestrichtian are probably confused with one of the other subspecies or are 

 erroneous. 



Globotruncana contusa patelliformis Gandolfi 



(PL 8, figs, la-c) 



1955 Globotruncana (Globotruncana) contusa patelliformis Gandolfi : 54-55, pi. 4, figs. la-c. 

 1961 Globotruncana contusa cf. patelliformis Gandolfi ; Corminboeuf : 112, pi. 1, figs. za-c. 



Description. Test large, robust ; trochospiraly coiled in the form a of high, 

 truncated cone with a subcircular, wide base ; dorsal side very highly raised, and 

 distinctly coned ; ventral side flat or even slightly concave as the sides gently slope 

 towards the umbilicus ; equatorial periphery almost circular, slightly lobate, with 

 two well-developed, heavily beaded marginal keels which become much closer on the 

 penultimate chamber and reduced to a single, limbate, non-beaded keel on the last 

 one ; the two keels enclose an almost horizontal and relatively wide peripheral 

 band which is gradually reduced towards the last chamber ; axial periphery sub- 

 angular, truncate ; chambers on the dorsal side are not all clear, probably 14 in 

 number, arranged in 3 dextrally coiled whorls ; initial chambers small, indistinct, 

 roughly globular, weakly inflated, increasing slowly in size and followed by crescentic, 

 inflated chambers which are strongly elongated in the direction of coiling and 

 increasing very rapidly in size ; the last whorl is composed of 4 very long, narrow, 

 slightly undulating, crescentic chambers which are distinctly elongated in the 

 direction of coiling and increasing slowly in size ; on the ventral side the chambers 

 are 4, very long, narrow, distinctly elongated and strongly overlapping ; the very 

 long sutures on the dorsal side are distinctly curved, strongly raised and heavily 

 beaded especially in the early part ; on the ventral side the sutures are short, strongly 

 curved forward, raised and beaded ; umbilicus roughly rectangular in outline, wide, 

 deep, surrounded by raised, beaded ridges and covered by complex tegilla of which 

 remnants are still preserved ; primary apertures interiomarginal umbilical ; tegilla, 



