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[[File:Fig 72.jpg|thumb|<font size="2"> '''Fig. 1.''' 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)]] [[File:Fig 79.jpg|thumb|<font size="2"> '''Fig. 2.''' Preseptal (prp) and postseptal (pop) passages. '''A:''' ''Alveolina munieri'' Hottinger (equatorial section of microspheric specimen, Middle Lutetian, S. Giovanni Ilarione, Northern Italy). '''B-E:''' unpublished plasticine models of the shell by M. Reichel. '''B-C:''' oblique views showing chamberlets. In C the chamber roof (spirotheca) is partly removed. '''D:''' side view of chamber showing septum and passages behind and in front of it. '''E:''' oblique view complementary to B showing main and intercalary apertures. the septal realm between two adjacent chambers. '''F-H:''' unpublished models of sarcode (=shell cavities) by M. Reichel seen from above (F), obliquely from the side (G) and from below (H); '''Arrows:''' direction of growth; '''bl:''' [[basal layer]]; '''chl:''' chamberlet; '''chlsut:''' chamberlet suture; '''chsut:''' chamber suture; '''f:''' [[foramen]]; '''icf:''' intercalary foramen; '''pop:''' postseptal passage; '''prp:''' preseptal passage; '''prwsurf:''' chamber roof surface of previous whorl; '''s:''' [[septum]]; '''sl:''' septulum; '''sup:''' supplementary passages in basal layer; '''sut:''' [[suture]] (of chambers); '''te:''' chamber roof (tectum); (Hottinger, 2006; fig. 79 [http://paleopolis.rediris.es/cg/CG2006_M02/index.html] '''CC'''/BY-NC-SA)]] __FORCETOC__ ==Definition== *''according to Hottinger (2006):'' '''PASSAGE''' – the means of communication between adjacent [[compartment]]s of the same [[chamber]]; it is an opening that may be sited below the frontal [[chamber wall]] (preseptal), after the septal wall (postseptal) as in alveolinids, or at the fusion between [[exoskeleton]] and [[endoskeleton]], as in verbeekinids. In peneropliform to concentric architectures, the passages may be semiannular-annular, in a preseptal position, as in ''Sorites'', or paired in lateral positions, separating [[exoskeleton]] from [[endoskeleton]], as in ''Anchispirocyclina'' or ''Orbitopsella''. ==See also== * [[endoskeleton]] * [[exoskeleton]] * [[preseptal passage]] ==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]] |
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