Dr. Nagy I. Zoltán szerk.: Fragmenta Mineralogica Et Palaentologica 7. 1976. (Budapest, 1976)
GENUS Gperculinoides HANZAWA 1935 Many authors have questioned the existance of this genus, and some of the them have considered as a subgenus of the genus Nummulites . SACHS (1957) assigned to the genus Operculinoides a number of nummulites species described by M. DE CIZANCOURT (1948; 1951), designated by her as cord nummulites "Nummulites cordelees". However SACHS has not given no diagnosis of this genus, neither has he defined the difference between this genus and the genus Nummulites . BIEDA (1963) mentioned that the genus Operculinoides is similar to some species of nummulites, namely those with a loose whorls, however he found that there is a distinct difference between the former and the latter. In the genus Operculinoides , the nucleoeonch is of the nephrolepidine type (the deuteroconch is larger than the protoconch, and partly embraces it). BIEDA concluded that the stratigraphie range of genus Operculinoides in the Carpathian Flysch, in America and in the Tatra Eocene begins in the Upper Eocene. However SACHS (1957) recorded Operculinoides bermudezi in the Paleocene of central America. The openion of the present author is that the genus Operculinoides belongs to a transitional genus between Nummulites and Operculina with involute test and rapidly increasing whorls,. (Table 1.). The present author observed in the studied section some specimens, which agree perfectly with HASSAN (1953) figures identified as Operculinoides daviesi . Operculinoides daviesi HASSAN, 1953 (pi. 2, fig. 3a, 3b; pi. 4, fig. 1) 1953 Operculinoides daviesi HASSAN, p. 11 , pl. 1, fig. 3. Test small, having an average diameter of 1.5 mm and an average thickness of 0.3 mm. The edge is sharf. The equatorial section shows 2* whorls. The spiral lamina is regular and thin. The whorling is lax expecially the last whorl which is three times higher than the preceeding one. The septa are numerous, vertical and curve only near the roof of the chamber. The chambers are much higher than wide. The axial section is characterized by its thin marginal cord, thin spiral lamina and a slightly prominent polar at the pole of the test. Occurence: This species has been found in the upper limestone beds of the Thebes Formation at Gabal El Shaghab. Distribution: HASSAN (1953) described this species from the Lower Libyan rocks in Kharga Oasis and gave it a Lower Paleocene age. Age: Lower Ypresian. FAMILY Nummulitidae SUBFAMILY Cycloclypeinae GENUS Heterostegina D'ORBIGNY, 1826 Heterostegina ruida SCHWAGER, 1883. (pl. 1; fig. 12)
