. Bulletin - United States National Museum. Science. STUDIES IN FORAMINIFERA 227 Type and occurrence: Holotype (BMNH P41659) here figured, from the Lower Crag (PHocene) of Sutton, Suffolk, England. ? Family Virgulinidae Cushman, 1927 Aeolostreptis Loeblich and Tappan, new genus Plate 72, Figure 20 Type species: Buliminella vitrea Cushman and Parker, 1936. Derivation: aiolos, Gr., changeable + streptos, Gr., twisted; gender feminine.) Test free, elongate, base bluntly rounded, the early portion in a low discorbine coil with sLx chambers per whorl, later reduced in number to three chambers per w
. Bulletin - United States National Museum. Science. STUDIES IN FORAMINIFERA 227 Type and occurrence: Holotype (BMNH P41659) here figured, from the Lower Crag (PHocene) of Sutton, Suffolk, England. ? Family Virgulinidae Cushman, 1927 Aeolostreptis Loeblich and Tappan, new genus Plate 72, Figure 20 Type species: Buliminella vitrea Cushman and Parker, 1936. Derivation: aiolos, Gr., changeable + streptos, Gr., twisted; gender feminine.) Test free, elongate, base bluntly rounded, the early portion in a low discorbine coil with sLx chambers per whorl, later reduced in number to three chambers per whorl, and becoming high spired; chambers few in number, at first low, later about equal in breadth and height, but never extremely high and elongate; sutures distinct, depressed; wall calcareous, finely perforate, granular in structure, surface smooth; aperture a loop at the inner margin of the final chamber, at right angles to the sutures, with a narrow lip at the forward margin. Remarks: Aeolostreptis, new genus, differs from Lacosteina Marie in the early coil being trochoid as in Discorbis Lamarck, rather than planispiral, and in there being a gradual increase in the height of the spii'e instead of an abrupt change in the plane of coiling from the early coil to the later spire. Buliminella Cushman differs in having a radial rather than granular wall structure and a tapered rather than bluntly rounded base, due to the type of chamber arrangement. Buliminella has an increasing number of chambers per whorl \vith later development, and has a complex internal toothplate, whereas Aeolostreptis has a decreasing number of chambers in later development. The majority of species with few chambers in the last whorl, placed in Buliminella by Cushman and Parker (1947), are in reality species referrable to Praebulimina Hofker, since typical Buliminella apparently is not foimd below the Eocene. Aeolostreptis, new genus, diflfers from Praebulimina in having the early many- chambered coil for
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