. Bulletins of American paleontology. 55 Trinidad Cretaceous GLOBicERnciDAE: Bronnimann 55 Hastigerinoides rohri n. sp. Plate 1, figs. 8, 9 Text fig. 29 DescnpfwTi.â^The small and regularly stellate test is planispiral ^nd semi-involute in the adult. It is possible that the early chambers are arranged in a weak trochoidal spiral. The 5 elongate chambers â of the adult only slightly increase in size during growth, and not much difference exists between the dimensions of the first and the last chamber of the final volution. The chambers are bulbose at the base and tapering more or less gradually
. Bulletins of American paleontology. 55 Trinidad Cretaceous GLOBicERnciDAE: Bronnimann 55 Hastigerinoides rohri n. sp. Plate 1, figs. 8, 9 Text fig. 29 DescnpfwTi.â^The small and regularly stellate test is planispiral ^nd semi-involute in the adult. It is possible that the early chambers are arranged in a weak trochoidal spiral. The 5 elongate chambers â of the adult only slightly increase in size during growth, and not much difference exists between the dimensions of the first and the last chamber of the final volution. The chambers are bulbose at the base and tapering more or less gradually into pointed ends, which as a rule are broken off. The regular stellate arrangement of the adult is a remarkable feature of this species. Deformations of the test are rather common. The shallow umbilici are usually filled Avith matrix. Traces of subglobular earlier chambers can occasionally be seen. The straight sutures are well defined and not much depressed. The aperture was not clearly seen; it appears to be a low arcuate opening at the base of the end chamber. The walls are thin and finely perforate. The surface is smooth. Dimensions.âThe maximum diameter of the paratypes including the elongate chambers varies from mm. to mm. Holotype.âHastigerinoides rohri Bronnimann. T. L. L. Cat. Nos. 144455, 168920. Plate i, figs. 8, g. Maximum diameter mm. Basal thickness of end chamber mm. Thickness of spine mm. Radial length of average chamber rnm, Glohotruncana apenninica zone, Gautier formation, Upper Creta- ceous, Trinidad, B. W. I. Deposited in Cushman Collection, U. 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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