IN THE ESNA-IDFU REGION, NILE VALLEY, EGYPT 121 



Stratigraphical range. Globotruncana havanensis was first described by 

 Voorwijk (1937) from the Upper Cretaceous of Habana, Cuba. It was also recorded 

 from the Maestrichtian of the Caucasus (Keller 1946 and Subbotina 1953), the 

 Maestrichtian of Trinidad (Bolli 1951, 1957a), of Austria (Papp & Kiipper, 1953), 

 of northeastern Colombia (Gandolfi 1955), of Bavaria (Knipscheer 1956), of Texas 

 and of Cuba (Bronnimann & Brown 1956), of northwestern Germany and of Holland 

 (Hofker 19566, c), of Australia (Edgell 1957), of Romania (Vinogradov i960) and of 

 southern Scandinavia (Hofker 1960a and Berggren, 1962). 



In the Esna-Idfu region, G. havanensis occurs as a rare form throughout the Mae- 

 strichtian, increasing gradually upwards in the section, and dying out completely 

 below the disconformity separating the Maestrichtian from the overlying Danian. 



Globotruncana leupoldi Bolli 

 (PI. 1, figs. 4«-c) 



1945 Globotnmcana leupoldi Bolli : 235, pi. 9, fig. 17 ; text-fig. 1, figs. 25, 26. 



Description. Test medium-sized, subcircular in outline, biconvex, coiled in 

 a moderately high trochospire ; dorsal side broadly convex, moderately raised, 

 ventral side convex and moderately inflated ; equatorial periphery subcircular, 

 distinctly lobate, with two well-developed, thickened, delicately beaded and widely 

 spaced marginal keels, becoming single on the last chamber only ; axial periphery 

 truncate in the early part, angular and distinctly acute in the later part ; chambers 

 on the dorsal side 16, arranged in 3 dextrally coiled whorls ; the initial chambers are 

 small, inflated, globigerine, increasing moderately in size and followed by typically 

 crescentic, petaloid chambers which increase slowly in size as added ; the last whorl 

 is composed of 5 large, typically crescentic, petaloid chambers which are elongated 

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

 are 5, large, roughly ovoid and distinctly outlined with horseshoe-shaped, beaded 

 ridges and increase slowly in size ; sutures on the dorsal side are curved, raised and 

 beaded ; on the ventral side they are strongly curved forward, thickened, raised and 

 beaded ; umbilicus pentagonal in outline, wide, deep, bordered by raised, beaded 

 ridges and covered by complex tegilla of which remnants are still preserved ; primary 

 apertures interiomarginal, umbilical ; tegilla with accessory apertures only poorly 

 preserved ; wall calcareous, perforate, except for the imperforate keels, peripheral 

 band and tegilla ; surface smooth. 



Dimensions of described specimen. 

 Maximum diameter = 0-45 mm. 

 Minimum diameter = 0-37 mm. 



Thickness = 0-22 mm. 



Remarks. Bolli (1945) described G. leupoldi from thin sections only and included 

 in its synonymy some of the forms previously described by de Lapparant (1918) 

 as Rosalina linnei d'Orbigny " type 5 " and Rosalina stuarti, although the latter is a 

 completely distinct form. He also considered some of the forms described by Vogler 



