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Notes on the Structure of an Early Dictyonema.

Published online by Cambridge University Press:  01 May 2009

O. M. B. Bulman
O. M. B. Bulman
Affiliation:
Beit Scientific Research Fellow of the Imperial College of Science and Technology.
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Summary

The more important points in connexion with the structure of D. flabelliforme are:—

1. The absence of any real approach to the spiral arrangement of the thecae along the stipes.1

2. The absence of a common canal; and the consequent budding of each hydrotheca direct from the preceding one.1

3. The initial constriction of each hydrotheca cavity.

4. The budding of the bithecae from the sides of the hydrothecae along which they lie.

5. The early stage at which the presence of the bithecae is observed.

6. The derivation, indifferently “right-handed” or “left-handed” of the crossing canal.

7. The nature of the dissepiments—hollow bars derived principally as outgrowths of the bithecae.

Type
Original Articles
Information
Geological Magazine , Volume 62 , Issue 2 , February 1925 , pp. 50 - 67
Copyright
Copyright © Cambridge University Press 1925

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References

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