Linked from
The 22 pages that link to Mammary gland, each with the reason it gives.
MarsupialRelated: Marsupial young attach to a teat supplied by a mammary gland.
MammaliaRelated: Milk production is the defining reproductive feature of living mammals.
ProlactinRelated: Its secretory cells are major targets of prolactin during lactation.
MonotremeRelated: Monotreme mammary glands release milk through skin openings rather than nipples.
SireniaRelated: Sirenians nurse their young despite spending their lives in water.
CowRelated: The cow's mammary glands produce and deliver milk through the udder.