Page 517 - Atlas of Histology with Functional Correlations

lingual tonsils can be seen in these folds (7).

The lamina propria (7) of the mucosa is wider but similar to the anterior two

thirds of the tongue. Under the stratified squamous epithelium (6) are
aggregations of diffuse lymphatic tissue (2) and adipose tissue (4), nerve
fibers (3) (in longitudinal section), blood vessels, an artery (8), and a vein (9).

Deep in the connective tissue of the lamina propria (7) and between the
interlacing skeletal muscle fibers (5) are mucous acini of the posterior lingual

glands (11) whose excretory ducts (10) open onto the dorsal surface of the
tongue, between bases of the mucosal ridges and folds (1, 7).

FIGURE 13.10 ■ Posterior tongue: behind circumvallate papillae and near
lingual tonsil (longitudinal section). Stain: hematoxylin and eosin. Low
magnification.

FIGURE 13.11 | Lingual Tonsils (Transverse

Section)

Lingual tonsils are aggregations of small, individual tonsils, each with its

tonsillar crypt (2, 8) that are situated on the dorsal surface of the posterior
region or the root of the tongue. A nonkeratinized stratified squamous
epithelium (1) lines the tonsils and their crypts (2, 8). The tonsillar crypts (2, 8)

form deep invaginations and may extend into the lamina propria (5).

Lymphatic nodules (3, 9), some with germinal centers (3, 9), are located in
the lamina propria (5) below the stratified squamous surface epithelium (1).
Dense lymphatic infiltration (4, 10) surrounds the individual lymphatic nodules
(3, 9). Also in the lamina propria (5) are fat cells of the adipose tissue (7) and

the secretory mucous acini of the posterior lingual glands (11). Small

516