. Bulletins of American paleontology. . Fig. 8. Rugoglobigcrina prtaloidra suhpctaloidea, , ; showing faint keel and hantkeninoid spines in the early chambers of the last \olution. S. 5595. Colon shale, Pullcnia crctacea zone. 60 X- CONTUSA BRANCH Globotruncana contnsa ooutnsa (Cushman) PI. 4, fig. 3a-c Glohotruncana area var. contusa Cushman 1946, pp. 150-151, pi. 62, fig. 6a-b. Description.—Chambers of the last coil with a sharply cut polygonal periphery conspicuously undulated, the second keel some- times completely disappearing. The chambers are occasionally slightly inflated,
. Bulletins of American paleontology. . Fig. 8. Rugoglobigcrina prtaloidra suhpctaloidea, , ; showing faint keel and hantkeninoid spines in the early chambers of the last \olution. S. 5595. Colon shale, Pullcnia crctacea zone. 60 X- CONTUSA BRANCH Globotruncana contnsa ooutnsa (Cushman) PI. 4, fig. 3a-c Glohotruncana area var. contusa Cushman 1946, pp. 150-151, pi. 62, fig. 6a-b. Description.—Chambers of the last coil with a sharply cut polygonal periphery conspicuously undulated, the second keel some- times completely disappearing. The chambers are occasionally slightly inflated, especially in the early stages. The umbilical lips are more arched and developed than in the previous species {rosetta type). Dimensions.—Width x mm.; thickness mm. Figured specimen.—No. 20850, Paleontological Research Insti- tution. Occurrence.—Upper Colon shale (upper Pullenia cretacea and Siphogenerinoides bramlettei zones); more frequent in shallower environment. Remarks.—\s was noted by Cita, 1948 (p. 8), and BoUi, 1951 (p. 196), Git. conica var. plicata White should be identical with this species. All transitional stages connect this form with Git. contusa patellijor^nis. Git. contusa contusa becomes more and more frecjuent higher in the section as compared with Git. contusa patelliformis. Cita, 1948, suggested that this form should be separated from Git. area, being somewhat closer to Git. calicijormis. Bolli, 1951, recognized its close relationship to Git. jornicata. Git. jornicata forni- cata and Git. calicijormis calicijormis are undoubtedly genetically. 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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