Endocrine system endocrine glands are, in general, their ductless nature, their vascularity, and commonly the presence of intracellular vacuoles or granules that store their hormones. In contrast, exocrine glands, such as salivary glands, sweat glands, and glands within the gastrointestinal tract, tend to be much less vascular and have ducts or a hollow lumen. A number of glands that signal each other in sequence are usually referred to as an axis, for example, the hypothalamic-pituitary-adrenal axis. In addition to the specialized endocrine organs mentioned above, many other organs that are part of other body systems, such as bone, kidney, liver, heart and
Ciaccio's glands Ciaccio's glands Ciaccio's glands or Wolfring's glands are small tubular accessory lacrimal glands ("glandulae lacrimales accessoriae") found in the lacrimal caruncle of the eyelid. They are located in the upper border of the tarsus, approximately in the middle between the extremities of the tarsal glands. Sometimes they are situated slightly above the tarsus. There are usually 2 to 5 of these glands in the upper eyelid, and their function is to produce tears which are secreted onto the surface of the conjunctiva. They are named after Italian anatomist Giuseppe Vincenzo Ciaccio (1824–1901), who described these glands in 1874. They are