The ultrastructure of ribbon - like deposits over the thecae in Orthograptus Gracilis Roemer

• Autorzy: Urbanek A. , Mierzejewska G.
• Języki publikacji: EN

Abstrakty

EN

The periderm of Orthograptus gracilis has bee studied with an electron microscope (TEM and SEM). Four components have been recognized within the thecal wall: 1. endocortex, 2. fusellar layer, 3. cortex and so-called 4. taeniocortex. Taeniocortex covering the outer surface of the thecal wall consists of ribbon or sometimes roller-like elements and is produced of a peculiar material. The data obtained do not confirm Andres' belief that ribbons are made of cortical material and that entire cortex was produced by deposition of ribbon-like units.

• Wydawca: -
• Czasopismo: Acta Palaeontologica Polonica
• Rocznik: 1978
• Tom: 23
• Numer: 4
• Opis fizyczny: p.637-642,ref.

Twórcy

autor

Urbanek A.

• Institute of Geology, University of Warsaw, Al.Zwirki i Wigury 93, 02-089 Warsaw, Poland

autor

Mierzejewska G.

• Institute of Paleobiology, Polish Academy of Science, Al.Zwirki i Wigury 93, 02-089 Warsaw, Poland

Bibliografia

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