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Reference
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| Title: |
Report on Referred Fossils
,
1962
(12/28)
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| Report by: |
Norman J. Silberling
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| Referred by: |
E. M. MacKevett
, Jr.
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| | Age: | Ladinian |
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| Comment: | The genus Daonella is generally restricted to the middle and upper part of the Middle Triassic and is supplanted by Halobia in the Upper Triassic, though some overlap of the two genera is possible in the lower part of the Upper Triassic. Daonella frami was originally described from Ellesmere Island in the Canadian Arctic and is assigned an Anisian or Ladinian age by Tozer (1961, Geol. Survey Canada Mem. 316) who has re-collected the type area. The ammonites listed by Tozer as being associated with D. frami seem like good evidence of a Ladinian (late Middle Triasic) age. The other species of Daonella in your collection is most like D. subquadrata which is known only from Japan in beds considered late Ladinian in age, though on what basis I don't know. |
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