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Eocetus
''Eocetus'' is an extinct protocetid early whale known from the early late Middle Eocene (Bartonian, ) Giushi Formation in Gebel Mokattam, (, paleocoordinates ) outside Cairo, Egypt.〔. Retrieved July 2013.〕〔. Retrieved July 2013.〕 Since the genus was first described in the early 20th century, several other specimens, mostly isolated vertebrae, have been attributed to ''Eocetus'', but the taxonomic status of these widely distributed specimens remain disputed.
==''E. schweinfurthi''==
described "''Mesocetus schweinfurthi''" based on a dorsoventrally compressed skull with only I2 ''in situ'', a specimen supposedly originating from a 40 Ma Tethyan deposit at Mokattam. Fraas also referred two isolated teeth, P4 and M1, to the skull and the most important of his specimens is not the deformed skull, but the upper molar which retains three roots and a worn but well-developed protocone. Georg August Schweinfurth, a German palaeontologist who explored Mokattam in the 1880s, mentioned the quarriers there very eagerly offered "shark teeth" to tourists and that scientists and fossil collectors regularly bought their specimens from this source. There is reason to assume that Fraas were among them and that at least his two isolated teeth were described without direct knowledge of their original locality and stratigraphic context. Notwithstanding that the stratigraphic information supplied by Fraas and his contemporaries can be difficult to interpret, the geology of Egypt is well-studied, and both the skull and the accompanying teeth are most likely Bartonian in age — older and significantly more primitive than any other cetacean specimen known from Egypt at that time. Fraas soon discovered that the name "Mesocetus" was already taken, and changed the name of his "Urform Protocetus" to ''Eocetus''.
Fraas also attributed two isolated vertebrae to his new genus, both of which moved to ''Basilosaurus drazindae''. attributed two other vertebrae from Mokattam to ''Eocetus''. These two vertebrae were lost for many years until described two bones that he discovered in a museum in Germany and appeared to fit Stromer's description. Uhen based his assignment of his own North American genus (see below) to ''Eocetus'' on the similarities to Stromer's vertebrae.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
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