Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-12-04T14:46:54.355Z Has data issue: false hasContentIssue false
  • English
  • Français

A Note on Costellae in Orthid and Strophomenid Brachiopods

Published online by Cambridge University Press:  01 May 2009

K. J. Kemežys
K. J. Kemežys
Affiliation:
P.O. Box 1101, Canberra City, Australia.
Get access Rights & Permissions [Opens in a new window]

Abstract

The costellae of a population of brachiopods can be quantitatively described by plotting the total number of costellae on a valve against the length of its margin. The resultant curve describes the continuous change of the average distance between adjacent costellae during growth. When costellae first appear, this distance has the value of about 0·06 mm and it increases during growth to various degrees in different brachiopod species.

If it is assumed that costellae mark the sites of setae, then the magnitude of the distance between adjacent costellae can be discussed in terms of the function of setae.

The magnitude of the parameters of the distribution of setae and punctae are compared to the silt/sand dividing line.

Type
Articles
Information
Geological Magazine , Volume 104 , Issue 5 , October 1967 , pp. 435 - 442
Copyright
Copyright © Cambridge University Press 1967

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Biernat, G., 1959. Middle Devonian Orthoidea of the Holy Cross Mountains and their ontogeny. Palaeont. polon., 10, 1–77.Google Scholar
Cooper, G. A., 1956. Chazyan and related brachiopods. Smithson. misc. Collns, 127, 1–1245.Google Scholar
Cowen, R., 1966. The distribution of punctae on the brachiopod shell. Geol. Mag., 103, 269–275.CrossRefGoogle Scholar
Kemežys, K. J., 1965. Significance of punctae and pustules in brachiopods. Geol. Mag., 102, 315–324.CrossRefGoogle Scholar
Lamont, A., 1934. Lower Palaeozoic Brachiopoda of the Girvan district: suggestions on morphology in relation to environment. Ann. Mag. nat. Hist., (series 10), 14, 161–184.CrossRefGoogle Scholar
Moss, A. J., 1966. Origin, shaping and significance of quartz sand grains. J. geol. Soc. Aust., 13, 97–136.CrossRefGoogle Scholar
Rudwick, M. J. S., 1965. Ecology and paleoecology. In Moore, R. C. (ed.), Treatise on invertebrate paleontology, part H, Brachiopoda, H199–H214.Google Scholar
Spjeldnaes, N., 1957. The Middle Ordovician of the Oslo region, Norway: 8. Brachiopods of the suborder Strophomenida. Norsk geol. Tidsskr., 37, 1–214.Google Scholar
Thomson, A. J., 1927. Brachiopod morphology and genera (Recent and Tertiary). N.Z. Board Sci. and Art Manual, 7, 1–338.Google Scholar
Walmsley, V. G., 1965. Isorthis and Salopina (Brachiopoda) in the Ludlovian of the Welsh borderland. Palaeontology, 8, 454–477.Google Scholar
Williams, A., and Rowell, A. J., 1965. Morphology. In Moore, R. C. (ed)., Treatise on invertebrate paleontology, part H, Brachiopoda, H57–H155.Google Scholar
Williams, A., and Wright, A. D., 1963. The classification of the “Orthis testudinaria Dalman” group of brachiopods. J. Paleont., 37, 1–32.Google Scholar