. Bulletins of American paleontology. 36 BULLETIK 140 36 pattern. All the investigated specimens are dextrally coiling. Dimensions.—The maximum diameter of the paratvpes is from mm. to mm. Holotype.—Rugoglobigerina {I^.ugoglobJgerina) rugosa rotundata Bronnimann. T. L. L. Cat. Nos. I5559i-i55594- Plate 4, figs. 7-9. Maximum diameter mm. End chamber: radial diameter mm.; tangential diameter mm.; thickness mm. Globo- truncana mayaroensis zone, Guayaguayare beds, Maestrichtian, Upper Cretaceous, Trinidad, B. W. I. Deposited in the Cushman Collection U. S. National M
. Bulletins of American paleontology. 36 BULLETIK 140 36 pattern. All the investigated specimens are dextrally coiling. Dimensions.—The maximum diameter of the paratvpes is from mm. to mm. Holotype.—Rugoglobigerina {I^.ugoglobJgerina) rugosa rotundata Bronnimann. T. L. L. Cat. Nos. I5559i-i55594- Plate 4, figs. 7-9. Maximum diameter mm. End chamber: radial diameter mm.; tangential diameter mm.; thickness mm. Globo- truncana mayaroensis zone, Guayaguayare beds, Maestrichtian, Upper Cretaceous, Trinidad, B. W. I. Deposited in the Cushman Collection U. S. National Museum, Washington, D. C. Occurrence.—Globotruncana mayaroensis zone. Common. Remarks.—The rather irregular, occasionally almost subglobular test with the large, axially elongated chambers of the last volution, and the deep and small umbilicus, differentiate this subspecies from other Rugoglobigerinas. In addition, the ornamentation is not so clearly developed in a meridional pattern as observed in typical rep- resentatives of the rugosa group. It is believed that R. rugasa rotun- data is an offshoot of the rugosa Text fig. 16. Rugngloh'igcrina rugosa rotundata Bronnimann. T. L. L. Cat. Nos. 155591-155594. Globotruncana mayaroensis zone, Guayaguayare beds, Upper Cretaceous. All appr. X 80. (a,b,c) Same specimen, umbilical, spiral and apertural Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Paleontological Research Institution (Ithaca, N. Y. ); Columbia University. Ithaca, N. Y. , Paleontological Research Institution [etc. ]
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