Light microscopical (a), scanning electron microscopic (b), and histological (Masson’s trichrome staining) structure of the lingual root in bear. Valp, vallate papillae; Fip, filiform papillae (c,d,e); Ap, annular pad; Gg, gastatory groove; Sg, salivary gland. For other abbreviations see Figure 1, 2 and 3. Red and black rectangles in (b) and (e) show higher magnification of a vallate papilla and a salivary gland accini.