They are derived from the neural crest and migrate into the epidermis in the 6th week of embryonic life. They are functionally immature during their migration. Melanocytes populate the epidermis. Melanocytes increase in number, differentiate, make premelanosomes. Melanocytes begin to make pigment.
Melanocytes decrease in number to level in mature epidermis.
Melanocytes transfer pigment to keratinocytes. Melanocytes begin to regionalize in the hair peg. Melanocytes complete regional migration into the hair bulb.