igo UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 



by its rough surface, less pronounced marginal keel and umbilical collar, flush dorsal 

 sutures and much wider, inward tapering, funnel shaped umbilicus. 



Berggren (1960^ : 99) considered G. lensiformis Subbotina to be a junior synonym 

 of G. acuta Toulmin. However, the present study showed that the two forms are 

 quite distinct. G. lensiformis is distinguished by its extremely narrow umbilicus, 

 while G. acuta has an extremely wide umbilicus with a large, beaded umbilical collar. 



Aubert (1963) described as G. acuta Toulmin, from the Paleocene of Western 

 Morocco, a form which most probably belongs to G. velascoensis parva Rey. 



Globorotalia acuta has possibly evolved from G. angulata angulata (White) or G. 

 angulata abundocamerata Bolli, although no direct evidence was recorded. 



Hypotypes. P.45590-91. 



Horizon and locality. Figured specimens, from sample No. 40, Gebel Owaina 

 section. 



Stratigraphical range. The species was first described by Toulmin (1941) from 

 the Salt Mountain limestones of Alabama which he considered as Lower Eocene, but 

 was proved by Loeblich & Tappan (1957a) to be of Upper Paleocene age. It was 

 also recorded from the Paleocene Soldado formation of Trinidad (Cushman & Renz 

 1942) ; from the various Paleocene formations of the Gulf and Atlantic Coastal 

 Plains (Cushman 1944 ; Shiffiett 1948 and Loeblich & Tappan 1957 a, b) ; from the 

 Paleocene of Cuba (Cushman & Bermudez 1948, 1949 ; Bermudez 1950) ; from what 

 was considered as Lower Eocene of Mexico, Carribbean region and the Middle East 

 (Grimsdale 1951) ; from the Mid-Pacific seamounts (Hamilton 1953) ; from the 

 Cretaceous-Tertiary passage beds of Morocco (Rey and Lys in Cuvillier et ah, 1955) ; 

 from the so-called Montian-Thanetian of Algeria (Magne & Sigal, ibid.) ; from the 

 Truncorotalia Zone of the Cretaceous-Tertiary passage beds of Tunisia (Dalbiez & 

 Glintzboeckel, ibid.) ; from the Paleocene of Lebanon (Lys & Renouard, ibid.) ; 

 from the Velasco formation of Mexico (Loeblich & Tappan, 1957a, b ; Bermudez 1961) 

 and from the Upper Paleocene Jicara formation of Puerto Rico (Pessagno i960). 



In the Esna-Idfu region G. acuta floods the G. velascoensis Zone of Upper Paleocene 

 age, starting at its base and dying out completely at its top. 



Globorotalia aequa Cushman & Renz 

 (PI. 21, figs. 4a-c) 



1942 Globorotalia crassata (Cushman) var. aequa Cushman & Renz : 12, pi. 3, figs. 3«-c. 



1946 Globorotalia lacerti Cushman & Renz : 47, pi. 8, figs. 11-12. 



1947 Globorotalia crassata (Cushman) ; Subbotina : 119-121, pi. 5, figs. 31-33, pi. 9, figs. 



I5-I7- 

 1953 Globorotalia crassata (Cushman) ; Subbotina (pars) : 211, pi. 17, figs. na-i2c, ? figs. 

 ■ja-ioc, non figs, i^a-c. 



1955 Truncorotalia crassata var. aeqgua (Cushman & Renz) ; Dalbiez & Glintzboeckel (in 

 Cuvillier et al., 1955) : 533, pi. 2, figs. ga-c. 



1956 Globorotalia praenartanensis Sjutskaya : 98, pi. 3, figs. 5<z-e. 



19576 Globorotalia aequa Cushman & Renz ; Bolli (pars) : 74-75, pi. 17, figs. 1-3, ? pi. 18, 

 figs. 13-15- 



