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Notes on Thecal Variation in Monograptus

Published online by Cambridge University Press:  01 May 2009

O. M. B. Bulman
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Abstract

Thecal modifications in certain Monograptids are discussed on a basis of restorations which distinguish the theca from the remainder of the “thecal segment” of Törnquist. There seems little support in those bi-form Monograptids examined for the view that the less modified thecae reflect an incomplete development, and in general the new thecal types appear to represent transformations which commonly originate proximally or at least are more highly developed proximally. A possible analogy between this colonial development and metamerism is suggested.

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Articles
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Geological Magazine , Volume 88 , Issue 5 , October 1951, pp. 316 - 328
Copyright
Copyright © Cambridge University Press 1951

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References

REFERENCES

Beer, G. R. de., 1940. Embryos and Ancestors. Oxford: Clarendon Press.Google Scholar
Calman, W. T., 1926. The Rhynie Crustacean. Nature, cxviii, 89–90.CrossRefGoogle Scholar
Challinor, J., 1945. A Graptolite Lineage from North Cardiganshire. Geol. Mag., lxxxii, 97–106.CrossRefGoogle Scholar
Elles, G. L., 1922. The Graptolite Faunas of the British Isles. Proc. GeoI. Assoc., xxxiii. 168–200.CrossRefGoogle Scholar
Jones, O. T., 1909. The Hartfell–Valentian Succession around Plynlimon and Pont Erwyd. Quart. Journ. Geol. Soc., lxv, 463–537.CrossRefGoogle Scholar
Lapworth, , Elles, & Wood, , 1901–1918. A Monograph of British Graptolites. Palaeont. Soc., London.Google Scholar
Münch, A., 1938. Einige grundlegende Fragen über Bau und Struktur von Monograptus Gein. und Barrandeograptus Bouc. Zeitschr. f. Geschie-beforsch., xiv, 31–70.Google Scholar
Smith, S., & Lang, W. D., 1930. Type-specimens of some Carboniferous Corals … Ann. Mag. Nat. Hist., 10, v, 177–194.CrossRefGoogle Scholar
Törnquist, S. L., 1899. Researches into the Monograptidae of the Scanian Rastrites Beds. Lunds Univ. Årsskr., xxxv, afd. 2, No. 1.Google Scholar
Westoll, T. S., 1950. (in ZUCKERMAN.) A discussion on the measurement of growth and form. Proc. Roy. Soc., B 889, 490–509.Google Scholar