Pigmentary demarcation lines. Comparison of Negroes with Japanese.

The natural pigmentary demarcation boundaries of the skin can be classified as: Group A--lines along the upper limb with variable trans-pectoral extension; Group B--lines along the lower limb; Group C--paired lines in median or paramedian course on the chest with midline abdominal extension; Group D--posteromedian demarcation; and Group E--bilaterally symmetrical, obliquely oriented hypopigmented macules on the chest. Groups A and C are the most distinct and occur in both Negroes and Japanese.