Paleozoic origin of the cycads /
| Main Author: | |
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| Format: | Book |
| Language: | English |
| Published: |
Washington :
United States Government Printing Office,
1976.
|
| Series: | Geological survey professional paper
934 |
| Subjects: |
| Item Description: | "Megasporophylls and associated plants parts from the Upper Pennsylvanian and Lower Permian rocks of the southwestern United States are interpreted as a lineage of cycads, derived from the pteridosperms. Cycadean foliage is thought to be derived from Paleozoic taeniopterids" |
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| Physical Description: | iii, 48 páginas, 5 hojas de láminas en blanco y negro : ilustraciones en blanco y negro. |