The nipple and the areola of the human female breast

The nipple is covered by an epidermis with a characteristically intricate understructure of ridges. There are numerous, large sebaceous glands in the nipple, some opening inside the milk ducts. The terminal segments of the milk ducts are surrounded by bundles of smooth muscle arranged in sphincter‐like patterns. There are relatively few nerve endings in the epidermis of the nipple and areola; these are Krause‐like endings, and a number of non‐descript nerve endings are found around the epidermal ridges. All of these nerves, and those around the apocrine and eccrine sweat glands in the areola, contain acetylcholinesterase. The tubercles of Montgomery are accessory mammary glands. Though mammary glands are said to be modified apocrine sweat glands, the two have neither gross, nor histological and histochemical resemblances.