Figure 79: Preseptal (prp) and postseptal (pop) passages.
A: Alveolina munieri (equatorial section of microspheric specimen, Middle Lutetian, S. Giovanni Ilarione, Northern Italy). B-E: unpublished plasticine models of the shell by . 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 F-H: unpublished models of sarcode (=shell cavities) by seen from above (F), obliquely from the side (G) and from below (H); Arrows: direction of growth.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).