Fig. 3 in Annular Chambers In Cretaceous Orbitolinidae (Larger Benthic Foraminifera): An Overview

Fig. 3 Annular chambers in Coskinolinella daguini Delmas & Deloffre (upper Aptian Reocín Formation of Spain; a–-c, d?, f), Coskinolinella santanderensis Ramírez del Pozo (early Albian of Spain; g-h), Pseudorbitolina schroederi Luger (upper Maastrichtian Tarbur Formation of Iran; e, i–j, k, m-n: reconstruction of Henson, 1948), and some comparisons with Gusicella minima (Henson) (upper Maastrichtian Tarbur Formation of Iran; l, o). a subaxial section. Note the presence of foramina (left side) of unknown distribution pattern throughout the test. b–c oblique sections. d Drawing of the dorsal side of an isolated specimen with two annular chambers highlighted in colours (modified from Hofker, 1965, fig. 1, without scale, illustrated as C. daguini it might in fact belong to C. santanderensis). e subaxial section. Note the concentric arrangement of foramina (radial tubular apertures sensu Henson, 1948) in line between subsequent chambers in the middle part of the annular chambers (solid red left in the test, dotted red in the reconstructed part). f tangential section; approximate position shown in b (1------2). g-h tangential section showing intercalary beams. i axial section of a megalospheric specimen (em = embryo). j Detail from Fig. 3e (axial section) showing aligned tubular apertures (= tubular foramina, t.f.) sensu Henson (1948). k Schematic drawing modified from Henson (1948, fig. 16a) showing aligned tubular foramina (t.f., arrows towards test base) and primary chambers (p.ch.) in axial section (arrows); t.a. aperture at test base. l Part of the test in axial section showing aligned tubular foramina at the transition marginal to central zone. m–n Tangential sections showing aligned main partitions (m: thin-section, n: reconstruction from Henson, 1948, fig. 16e). o Part of the test in tangential section showing from left to right the cellular subepidermal network, and aligned vertical main partitions and tubular foramina.