Submandibular gland. Light micrograph of a section through a normal submandibular gland, one of a pair of salivary glands situated beneath the base of the tongue. The glands are divided into numerous lobules by stretches of connective tissue. The purple regions at upper centre and far right are secretory tissue which produces part of the saliva. The dark blue region at left is a septum containing excretory ducts (purple-lined rings) and blood vessels (red-filled). Magnification: x100 at 35mm size.