Hardy,1 in 1853, under the designation of "syphilide pigmentaire du col" was the first to describe leukoderma colli. This type of syphilitic vitiligo has since been described by many syphilographers. It occurs most frequently in the sixth to the twelfth month after infection but may appear much later. Those affected are usually women under 35 years, the sites of predilection being the neck and adjoining cutaneous surfaces. The lesions are either discrete or confluent depigmented macules, round, oval or irregular, and from 0.5 to 1.5 cm. in diameter or larger. If discrete, they are separated by areas of normal or hyperpigmented skin. This gives the neck a peculiar mottled appearance, in accordance with the old description of a neck that has been sunburned through lace.
Various theories for the production of these lesions have been advanced. Some assert that the dark areas, others that the light areas, are on