Ultrastructure of the acinar cells in the submandibular gland of the nine-banded armadillo.

There are two discrete lobes comprising the armadillo submandibular gland. These two lobes can be defined grossly, histochemically and morphologically with the light and electron microscope. The minor lobe stains more intensely with PAS and AB. When viewed in the electron microscope, the secretory granules of the acinar cells within this lobe appear mucous-like. The granules of the demilune cells are slightly different in appearance. The secretory granules of the acinar cells in the major lobe contain many dense foci embedded in a fibrillar matrix, a substructure not described previously. The demilune cells of this lobe contain secretory granules with a mucous-like structure which is consistent throughout the entire lobe. As in the minor lobe, these demilune cells stain very intensely with PAS and AB.