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The dimensions of the graptolite zooid

Published online by Cambridge University Press:  01 May 2009

Margaret Sudbury
Affiliation:
Thorpe Cottage, Chestnut Avenue, Thornton Dale, Pickering, North Yorkshire YO18 7RW, U.K.

Abstract

Measurements of fuselli and cortical bandages on thecae which show both of these enable a hypothesis about the dimensions of graptolite zooids to be put forward. This leads to a method for estimating zooid size when fusellus height alone can be measured. Results are shown for some species and the implications for theca formation and reproduction are discussed.

Type
Rapid Communication
Copyright
Copyright © Cambridge University Press 1991

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