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The Mode of Cladial Generation in Cyrtograptus

Published online by Cambridge University Press:  01 May 2009

R. Thorsteinsson
R. Thorsteinsson
Affiliation:
Geological Survey, Ottawa, Canada.
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Abstract

The morphology of Cyrtograptus rigidus Tullberg n. subsp. A is described from uncompressed material. Particular attention is directed to the sequence of development of the connecting structure of cladium and main branch, which is demonstrated with the aid of figured growth stages of cleared and uncleared specimens. Also discussed is the intimate relationship of relative rate of growth of characters of cladium to those on the main branch. Cursory study of numerous other uncompressed species of Cyrtograptus in the author's collection reveals that the principles of cladial development outlined here are of general application.

Type
Articles
Information
Geological Magazine , Volume 92 , Issue 1 , February 1955 , pp. 37 - 49
Copyright
Copyright © Cambridge University Press 1955

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References

REFERENCES

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