Sebaceous gland glands are in the areola that surrounds the nipple in the female breast. These glands secrete an oily fluid that lubricates the nipple, and also secrete volatile compounds that are thought to serve as an olfactory stimulus for the newborn. During pregnancy and lactation these glands, also called Montgomery's glands, become enlarged. Meibomian glands, in the eyelids, secrete a form of sebum called meibum onto the eye, that slows the evaporation of tears. It also serves to create an airtight seal when the eyes are closed and its lipid quality also prevents the eyelids from sticking together. The meibomian glands
Apocrine sweat gland ducts. The tubules are wrapped in myoepithelial cells, which are more developed than in their eccrine gland counterparts. In hoofed animals and marsupials, apocrine glands act as the main thermoregulator, secreting watery sweat. For most mammals, however, apocrine sweat glands secrete an oily (and eventually smelly) compound that acts as a pheromone, territorial marker, and warning signal. Being sensitive to adrenaline, apocrine sweat glands are involved in emotional sweating in humans (induced by anxiety, stress, fear, sexual stimulation, and pain). In a five-month-old human fetus, apocrine glands are distributed all over the body; after a few weeks, they exist in