Plate 4, figs. 1-9. Rhabdorites malatyaensis (Sirel, 1976). 1: oblique longitudinal section showing alignment of septula in successive chambers and an empty central chamber lumen and septa with multiple intercameral foramina. 2: Early juvenile stage in off-centered axial section. In addition above, an equatorial section of Archaias operculiniformis Henson, 1950, and on the bottom right an oblique section of "Peneroplis" cf. dusenburyi Henson, 1950. 3: oblique section at a high angle to the adult shell axis. 4: axial section of spiral nepiont with embryo. 5: axial section of microspheric nepiont. At top left a centered subaxial section of Archaias operculiniformis Henson, 1950. 6: oblique section nearly perpendicular to the axis of the adult shell. Note the arrangement of the multiple foramina in radial rows alternating with the septula. 7: oblique section at about 45° to the axis of the adult shell. 8: oblique section almost perpendicular to the axis of the adult shell. Note the radial pattern in the disposition of the foramina on the septal face. 9: oblique section inclined at about 60° to the axis of the shell; figs. 10-14. Praerhapydionina delicata Henson, 1950. 10: Section nearly perpendicular to the shell axis. Note the large, single foramen in the septum. The protruding peristomes responsible for the original stellar outline of the foramen have been cut away. 11: longitudinal section nearly parallel to the shell axis of a microsheric specimen with a short nepionic spire. Note the alignment of the septula in successive chambers. 12: longitudinal section parallel to the axis of the adult shell. 13: subaxial section of the adult shell showing a single central foramen in the late chambers. 14: longitudinal section of megalospheric shell; fig. 15. Haymanella huberi (Henson, 1950) (bottom) and Rhabdorites malatyaensis (Sirel, 1976) (top), oblique sections inclined at about 70° to the axis of the adult shell.
Abbreviations: chs: chamber suture; f: foramen; pst: peristome; rp: radial partition; s: septum; sl: septulum; sl*: region where the alignment of the septula in successive chambers is clearly visible; so: socculus.