Redrawn and relabeled from Paulli (1900). Cross-sections, in downwardly leaning frontal planes (see Maier and Ruf, 2014, for further information) through the ethmoturbinal region of the nasal cavity of Hystrix&cristata&(A) and Hydrochoerus&hydrochoerus&(B). Turbinals and recesses are labeled according to the terminology used in this paper. Hystrix&may have more turbinals overall than any other rodent. Hydrochoerus&is notable for the advanced degree of pneumatization. fs, frontal sinus; ft, frontoturbinal; it, interturbinal; scl, semicircular lamina; I, II, III, IV, V, ethmoturbinals I to V; ? pneumatic expansions of uncertain homology.

  Part of: Smith TD, Bonar CJ (2022) The nasal cavity in agoutis (Dasyprocta spp.): a micro-computed tomographic and histological study. Vertebrate Zoology 72: 95-113.