Fig. 6From: Ontogeny and morphology of the retrochoanitic septal necks of Agoniatites vanuxemi from the Middle Devonian Cherry Valley Limestone Agoniatites vanuxemi. PRI 68139. Septal necks cut above/below the median plane. a Rough texture visible at the adapical end of septal neck; smooth texture at adoral end. Scale bar 100 μm. b Rough texture visible at the adapical end of septal neck. Scale bar 100 μm. c, d Section below median plane. Rough texture visible at adapical end; smooth texture of septal neck visible at adoral end. Scale bar 200 μm. d Close-up from c, showing rough texture at adapical end of septal neck. Scale bar 20 μm. SN septal neck, rt rough texture, st smooth texture, V venter, S septum, arrow adoral directionBack to article page