| 21. | Septal necks short with wide brings that may be in contact with posterior surface of septa.
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| 22. | In the later part of the shell she segments are expanded and septal necks become recumbent.
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| 23. | Primitive forms are minute cyrtocones with closely spaced septa and a marginal siphuncle bearing sort septal necks.
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| 24. | Septal necks are holochoanitic to slightly maxichaonitic, extending back to the previous septum and sometimes beyond.
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| 25. | Septal necks, according to Teichert, 1964, are holochoantic, reaching to the previous septum.
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| 26. | The siphuncle is primitive with the septal necks pointing to the rear, a condition known as retrosiphonate.
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| 27. | The siphuncle in " Mensicoceras " is large with short septal necks and thin connecting rings.
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| 28. | Septal necks are short but not vestigial; connecting rings are thick; endosiphonal organic deposits are unknown.
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| 29. | Septal necks are hemichoanitic, the source of the name, and reach halfway to the previous septa.
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| 30. | The early segments in the siphuncle ( Techert 1964 ) are bulb shaped and the septal necks are short.
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