Figure 58: Hemiseptula in Amphistegina lessonii d'Orbigny from the Gulf of Aqaba, Red Sea. Recent.
A: the dorsal surface of a megalospheric specimen. Incident light. B: the inner surface of a fragment of dorsal chamber walls showing septa and hemiseptula broken at a short distance from the level of the eggholders. Note the three-layered texture of the septa (a primary bilamellar wall plus a septal flap) and the two-layered nature of the hemiseptula that results from the folding of the inner lamella. SEM graph.
egh: eggholder; hs: hemiseptula; s: septa.