154 UPPER CRETACEOUS-LOWER TERTIARY FORAMINIFERA 



although Globoconusa quadripartitaformis Khalilov 1956 was described as having a 

 convex, rather than a turreted dorsal side. Globoconusa conusa Khalilov is a junior 

 synonym of Globigerina daubjergensis Bronnimann 1953 a species which shows a 

 marked variation in the height of its spire. Again, variation in the degree of eleva- 

 tion of the dorsal side is clearly observed within one and the same species, and between 

 one species and another, and cannot be accepted as a generic character. Typical 

 globigerinas with a highly raised dorsal side are known, and in the other closely 

 related planktonic genera, forms with planoconvex, biconvex and spiroconvex test 

 are included within the same genus and cannot be separated on the basis of the 

 shape of the dorsal side. 



Loeblich & Tappan (1964) emended the diagnosis of Globoconusa Khalilov adding, 

 that the wall is characteristically spinose and that the aperture is a small, rounded 

 umbilical opening, with one or more tiny, secondary sutural openings on the spiral 

 side against the early whorl. However, they stated " Although Globoconusa was 

 described as high-spired, the type species is quite variable as to height of spire." 

 Again the holotype of Globoconusa conusa was described as having an umbilical 

 aperture only, with no sutural apertures, as was its senior synonym Globigerina 

 daubjergensis Bronnimann. Finally, if the surface spines are considered character- 

 istic of the genus, it would not be possible to decide to which genus forms such as 

 Globigerina kozlowskii Brotzen & Pozaryska (with a highly turreted spiral side and a 

 delicately papillose surface) should be assigned. 



Globoconusa Khalilov, as originally defined by its author, is a junior synonym of 

 Globigerina d'Orbigny 1826. Forms with minute sutural apertures which were 

 assigned to this genus by Loeblich & Tappan (1964) are not typical and should 

 preferably be treated separately. 



Morozova (1959) described Globigerina (Eoglobigerina) as a new subgenus, with 

 G. (E.) eobulloides Morozova as type species. It was said to differ from Globigerina 

 (Globigerina) d'Orbigny in its thin and smooth or microcellular test wall, and in the 

 small size of its aperture. However, surface texture and size of aperture are charac- 

 ters of specific rather than subgeneric importance. Furthermore, since Globigerina 

 (Eoglobigerina) eobulloides is a junior synonym of Globorotalia pseudobulloides 

 (Plummer), G. (Eoglobigerina) is a junior synonym of Globorotalia Cushman. It 

 should be noted that Morozova apparently included within Globigerina (Eoglobiger- 

 ina) some Senonian species of Hedbergella, thus considering its range to be Senonian to 

 Danian. 



Brotzen & Pozaryska (1961) described Subbotina as a new genus, with Globigerina 

 triloculinoides Plummer 1926 as the type species. Subbotina was said to differ from 

 Globigerina d'Orbigny in having a reticulate surface with large pores which open on 

 the surface in two funnel-shaped structures surrounded by a coronet or radiating 

 pillars. These authors studied the wall structure of Globigerina bulloides d'Orbigny 

 and concluded that it is completely different from the reticulate wall of Globigerina 

 triloculinoides. As they found no transitional stages between these two types of wall 

 texture, they separated the globigerinas with a reticulate surface as their new genus 

 Subbotina, stating that " Le type reticule . . . se trouve dans tout un group de 



