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标题：Some abnormally coiled ammonites from the Upper Cretaceous of Angola. American Museum novitates ; no. 1222
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作者：Haas, Otto ; Washburne, Chester Wesley
期刊名称：American Museum Novitates
印刷版ISSN：0003-0082
电子版ISSN：1937-352X
出版年度：1943
卷号：1943
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出版社：American Museum of Natural History
摘要："The fossils from the locality 'S-3' (= '2054'), which has yielded a new species of Axonoceras, a genus hitherto known only from the Maestrichtian Navarro group of Texas, and from 'S-22,' where a species characteristic of the same group (Nostoceras helicinum) has been found, are undoubtedly of Maestrichtian age. The same can be assumed for locality 'E-50' (= '2003'), as Baculites anceps is generally considered a Maestrichtian species (see Roman, 1938, p. 53). the typical, small North American species of of the genus Solenoceras which most resemble S. bembense, new species, from locality '2073' near Bembe occur in the Maestrichtian Navarro group of Texas as well as in the Pierre Shale of Missouri and in the Crosswicks Clay of Delaware, both of which are of Campanian age (see Carter, 1937, pp. 251-256; Stephenson, et al., 1942, correlation chart). Another small Solenoceras, S. miminum [sic] from Madagascar, is of late Maestrichtian age. Locality '2073' has thus to be considered Maestrichtian or Upper Campanian, and the same may be true of the undetermined ammonites, dealt with in the appendix, from the nearby locality '2004' (= '30'). The age of the present assemblage, on the whole, is, therefore, recognized to be Maestrichtian and perhaps in part also Campanian. In consequence, the so-called Teba formation of Angola, thought by Haughton (1924, p. 82) to correspond to the Campanian, but probably also Lower Senonian, seems also to include strata of Maestrichtian age. Paleogeographically, the evidence of the presence of a neritic sea in Angola, previously (Spath, 1921b, p. 56; Haas, 1942a, p. 21) established for the time extending from the Albian to the Campanian, can now be farther expanded to include also the Maestrichtian. This result was anticipated by Spath as early as 1922 (p. 155), when he mentioned 'the introduction ... of Maestrichtian ammonoids as far as Angola.' Particularly interesting is the close affinity of the present assemblage with the Navarro fauna of Texas; it strongly suggests for the Maestrichtian epoch an open sea connection between the neritic seas of Texas and Angola"--P. 16.