Pachydiscus (Ammonoidea) from Campanian (Upper Cretaceous) rocks in the Western Interior of the United States
Examples of the Campanian-Maastrichtian ammonite genus Pachydiscus Zittel, 1884, occur as great rarities in the Western Interior of the US. Pachydiscus (Pachydiscus) cf. oldhami (Sharpe, 1855) and P. (P.) cf. arkansanus (Stephenson, 1941) are recorded from the Baculites compressus zone of Montana, a...
| Main Authors: | , |
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| Format: | Journal article |
| Language: | English |
| Published: |
1991
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