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