Figure 6.

Frontal of Xenotyphlops grandidieri in (A) posterior, (B) anterior, (C) lateral, (D) medial, (E) ventral, and (F) dorsal view. amf.l, lateral wall of anterior medial foramen; bc, braincase; f.?, unknown foramen; nc, nasal cavity, nostril; nl, nasal lappet; nl.g, nasal lappet groove; nno, nostril nerve opening; of, optic foramen; or, optic recession; osn, osseous septum nasi; pwc, posterior wall of the choana; spF, subolfactory process of the frontal; V₁, trigeminal; V₂.mx, maxillary (V₂) branch of the trigeminal; vr, vertical ridge; vr.PfF, prefrontal‐frontal vertical ridge.