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''Fabiania'' is a large fossil benthic calcareous foram with a range extending from the Upper Paleocene to the Upper Eocene. The test, which is up to 4 mm in diameter, is in the shape of a more-or-less flattened cone with hollow center and bluntly rounded apex. The outer wall is thick and finely perforate, umbilical side and partitions imperforate, surface smooth to papillate: aperture in the earliest chambers a simple arch, later with a single row of large openings leading into the broad open umbilicus. The test begins with three thick-walled and perforate globose chambers. followed by a few chambers about one-half coil in length. with later chambers added in cyclic series or tiers. Short horizontal and vertical partitions arising from the inside of the outer wall form numerous coarse alveoli that, in turn, are subdivided by second order partitions into smaller alveoli. Horizontal sutures formed by the chamber tiers are depressed and distinct. Alveolar partitions are evident externally only on abraded specimens. ''Fabiania'' was named by A. Silvestri, 1924, and is assigned to the Cymbaloporidae, Planorbulinacea, Rotaliida. ''Fabiania'' is included in the Fabianiinae which also includes ''Eofabiania'' from the middle Eocene of California and ''Gunteria'' from the middle Eocene of the Caribbean region, and is distinct in having a world-wide distribution and a larger stratigraphic range. ==References== * A. R. Loeblich and H. Tappan, 1964. Sarcodina Chiefly "Thecamoebians" and Foraminiferida; Treatise on Invertebrate Paleontology, Part C Protista 2. Geological Society of America and University of Kansas Press. *A. R. Loeblich & H. Tappan,1988. (Forminiferal Genera and their Classification. ) GSI E-book 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Fabiania (foram)」の詳細全文を読む スポンサード リンク
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