View source for Interseptal pillars

[[File:Fig 47.jpg|thumb|<font size="2">'''Fig. 1.'''  Endoskeletal patterns in discoidal shells.
'''A-D:''' disposition of apertural axes. '''A:''' radial axes alternating in radial position from one stolon layer to the next. This is the most common disposition in imperforate forms with annular stages of growth. '''B:''' radial axes superposed in radial position on all stolon planes. '''C:''' crosswise-oblique stolon axes alternating in radial position from one stolon plane to the next. '''D:''' crosswise-oblique stolon axes superposed on all stolon planes. This pattern characterizes all members of the orbitolitid family. Schematic, not to scale. '''E-H:''' all endoskeletal elements are disposed in accordance with the basic patterns of the foraminal axes: E corresponds to pattern A, F to pattern B, G to pattern C and H to pattern D. Stereographs after Hottinger, 1967. Schematic, not to scale. In reality, the patterns are often disturbed by intercalary elements generated as the diameter of the annuli increases during growth. This maintains on the apertural face the mean distances between apertures and their mean diameter constant during ontogeny. Examples: E1-2: ''Pseudotaberina malabarica'', megalospheric generation, from Iran. Middle Miocene. '''E1:''' oblique-centered section of spiral-involute stage showing radial disposition of pillars. Laterally, there is a layer of short septula. '''E2:''' a transverse section tangential to a septum shows the alternating disposition of the foramina and the pillars. '''F1-2:''' New genus (possibly related to ''Pastrikella'') from the Pyrenean Upper Cretaceous in Northern Spain. The endoskeleton consists only of septula. There is but one median annular preseptal passage and it occupies the total radial extension of the annular chamber. There are only two planes of stolons. '''F1:''' an oblique section at a low angles with respect to the equatorial plane shows the radial disposition of the apertural axes and of the septula. '''F2:''' a transverse section parallel to the shell axis shows that the stolon axes on the two stolon planes are superposed. '''G1-3:''' ''Amphisorus'' from Rottnest Island near Perth, Australia. Recent. '''G1:''' the detail of an equatorial section demonstrates the crosswise-oblique disposition of the pillars on neighboring stolon planes. G2, an equatorial section, demonstrates that pillars are restricted to the equatorial zone of the disc. '''G3:''' a transverse section parallel to the shell axis and tangential to an annular septum shows the disposition of the median foramina and pillars altermating in radial position on successive stolon planes. They are flanked by two annular preseptal passages separating them from a lateral layer of septula subdividing the annular chamber. '''H1-2:''' ''Orbitolites spp.'' from the region of Tremp, Lerida prov., Northern Spain. Pyrenean Lower Eocene (Ilerdian). '''H1:''' the comparatively regular disposition of the ramps in sections parallel to the equatorial plane reveals their superposition in consecutive stolon planes. '''H2:''' in the transverse section parallel to the axis of the shell this superposition is clearly visible where the section is tangential to an annular septum.
Abbreviations: '''b:''' beam; '''f:''' foramen; '''pi:''' pillar; '''prp:''' preseptal space; '''ra:''' ramp; '''s:''' septum; '''sl:''' septulum; (Hottinger, 2006; fig. 47E-G)[http://paleopolis.rediris.es/cg/CG2006_M02/index.html] '''CC'''/BY-NC-SA)]]

[[File:Fig 72.jpg|thumb|<font size="2"> '''Fig. 2.''' The structure of ''Orbitopsella'': a simple [[exoskeleton]] and a pillared [[endoskeleton]] in a discoidal shell: ''Orbitopsella dubari'' Hottinger, Bou Dahar, Eastern Morocco, Middle Lias. Transmitted light micrographs.
'''A:''' oblique section of complete microspheric specimen; '''B:''' oblique section of microspheric specimen. The septa of the thickened margin are cut tangentially and reveal the alternating pattern in the disposition of foramina on the septal face. '''C:''' oblique tangential section of a microspheric specimen at a low angle to the equatorial plane showing a part of the disc with its exoskeleton (restricted to beams). Note the large open spaces, the lateral annular passages (arrows), that separate exoskeleton and endoskeleton. '''D:''' Oblique centered section of megalospheric specimen. Note the structured wall of the embryo, that shows it to be a sphaeroconch. '''E:''' Transverse section (parallel to the axis of coiling) of a megalospheric specimen. The septum in this tangential section reveals the alternating pattern of the apertures. '''F:''' schematic model of structure after Hottinger, 1967; not to scale;  '''green''': exoskeleton; '''brown''': endoskeleton'''; a:''' [[aperture]]; '''ap:''' [[annular passage]]; '''b:''' [[beam]]; '''f:''' [[foramen]]; '''p:''' [[pillar]]; '''pr:''' [[sphaeroconch]]; '''s:''' [[septum]]; (Hottinger, 2006; fig. 72 [http://paleopolis.rediris.es/cg/CG2006_M02/index.html] '''CC'''/BY-NC-SA)]]
__FORCETOC__
==Definition==
*''according to Hottinger (2006):''
'''INTERSEPTAL PILLARS''' - (pillars; lamelliform buttresses); in porcelaneous and agglutinated species: the multiple columnar projections between consecutive septa and parallel to protoplasmic flow. Pillars are part of the [[endoskeleton]]. To be distinguished from piles of lamellae.


==References==
Hottinger (1967), Foraminifères imperforés du Mésozoïque marocain.- Notes et Mémoires du Service géologique, Rabat, N° 209, p. 5-168

Hottinger (2006), [http://paleopolis.rediris.es/cg/CG2006_M02/index.html Illustrated glossary of terms used in foraminiferal research]. [http://paleopolis.rediris.es/cg/uk-index.html Carnets de Géologie], [http://paleopolis.rediris.es/cg/CG2006_M02/index.html Memoir 2], ISSN 1634-0744               
                          | [[Foraminifera]]  |  [[EForams-LINKS|FORAM-Links]] | [[CONTRIBUTORS|Contributors]]  |