Plate 11. GLOBOTRUNCANIDAE 



Figures la-c. Abathomphalus mayaroensis (Bolli) 43 

 la, Spiral side of hypotype (USNM P4833). 

 lb, Umbilical side, showing partially open pri- 

 ' mary extraumbilical-umbilical aperture and ir- 

 regular continuous umbilical tegillum with ac- 

 cessory infralaminal apertures. Ic, Edge view. 

 From the Maestrichtian Guayaguayare formation 

 of Trinidad, B.W.I. X 90. 



Figures 2a-c. Rugoglobigerina rugosa (Plummer) 43 



2a, Spiral side of hypotype (USNM P3929), 

 showing characteristic ornamentation. 2b, Um- 

 bilical side, showing well developed tegillum with 

 both intralaminal and infralaminal accessory 

 apertures. 2c, Edge view, showing meridional 

 pattern of ornamentation. From the Navarro 

 (Upper Cretaceous) of Texas. X 105. 



Figures 3a-4c. Rugoglobigerina scotti Bronnimann 43 

 3a, Spiral side of hypotype (USNM P4838). 

 3b, Umbilical view, showing development of 

 tegilla from successive chambers, and extending 

 across umbilicus. 3c, Edge view, showing infra- 

 laminal accessory apertures. From the Mae- 

 strichtian Navarro (Upper Cretaceous) of Texas. 

 4a, Spiral side of holotype (USNM P48S6) of 

 species described as type of Trinitella Bronni- 

 mann. 4b, Umbilical side, from which umbilical 

 tegilla have been broken during course of preser- 

 vation. 4c, Edge view. From the Maestrich- 

 tian Guayaguayare formation of Trinidad, B.W.I. 

 Figs. 3a-c, X 115; figs. 4a-c, X 120. 



Figures 5a-c. Rugoglobigerina hantkeninoides Bron- 43 



nimann 



5a, Spiral sides of holotype (USNM P4847), 

 248 



showing radially elongate early chambers con- 

 sidered basis for the subgenus Plummerella ( = 

 Plummerita, new name) Bronnimann, and the 

 meridional pattern of ornamentation. 5b, Um- 

 bilical side, with tegilla somewhat obscurely pre- 

 served. 5c, Edge view. From the Maestrich- 

 tian Guayaguayare formation of Trinidad, 

 B.W.I. X 150. 

 Figures 6-1 Ic. Globotruncana area (Cushman) 44 



6, Umbilical side of hypotype (USNM P4242a), 

 showing well developed umbilical tegilla, and 

 absence of open primary aperture. 7a, Spiral 

 side of excellently preserved hypotype (USNM 

 P4242b). 7b, Umbilical side, showing completely 

 preserved tegilla, which cover entire umbilical 

 region and obscure primary aperture. 7c, Edge 

 view. 8, 9, Umbilical side of hypotypes (USNM 

 P4242c-d) showing variation in development and 

 preservation of tegilla. 10, Umbilical side of 

 hypotype (USNM P4242e) showing tegilla broken 

 out of center as is most common in the poorly 

 preserved or prepared specimens of the genus. 

 The primary umbilical aperture can be seen here, 

 although in life it was always covered. Speci- 

 mens such as this have led to the common mis- 

 conceptions as to the distinctions between 

 Globorotalia and Globotruncana. From the 

 Navarro (Upper Cretaceous) of Texas. 11a, 

 Spiral side of holotype (Cushman Coll. 5078). 

 lib. Umbilical side, showing poor preservation 

 of the type with umbilical region obscured, lie. 

 Edge view. From the Mendez shale of Mexico. 

 All X 80. 



