Rostral to caudal CT slices of Dasyprocta leporina, spanning the space of the frontal recess (numbers indicate rostrocaudal CT slice level). The semicircular lamina is tinted red; frontoturbinals are tinted green. Slice 1278 is near the rostral ends of the first three frontoturbinals (ft1–3), at a position where the semicircular lamina (sl) would obscure view of these turbinals from the medial side. Note the horizontal lamina (hl) is a ventral attachment for ft2 and ft3. At slice 1278, note the frontal recess (fr) is the space dorsal to the hl, and a very compressed maxillary recess (mr) is positioned ventrolateral to the hl. At slice 1343, a fourth frontoturbinal (ft4) has emerged, and this turbinal gradually projects parallel to F1–3 at more caudal levels. At slice 1478, the emergence of an interturbinal (it) between ft2 and ft3 is visible. All frontoturbinals become double-scrolled caudally; the more ventromedial lamella ultimately fused with the cribriform plate (cp). or, olfactory recess. Scale bar: 3 mm.