Fig. 5. (A) Sagittal (vertical) section through the hyolingual apparatus of a Chamaeleo oustaleti (trichrome stain). Whereas the proximal part of the m. hyoglossus (near its origin) runs approximately straight alongside the second hyoid cornua (not visible in this plane of section), the distal part of the tongue retractor muscle (m. hyoglossus) is folded in a complex manner in three dimensions. Anteriorly, the m. hyoglossus inserts onto the connective tissue sheet surrounding the m. accelerator (not shown here). (B) Frontal (horizontal) section through the hyolingual apparatus in a Chamaeleo jacksonii (Verhoeff’s elastin stain). The folded tongue retractor and hypoglossal nerve are clearly visible. Centrally, the connective tissue sheet sends off branches of elastin fibres running into the folds of the m. hyoglossus. Here too, the folding of the retracted m. hyoglossus can be observed. MHG, m. hyoglossus.