Introduction In 1949 Sugar and Barber reported two cases of so-called pigmentary glaucoma as a new and rare clinical entity occurring in young males.1In 1951 Sugar added an additional case, when his monograph on the glaucomas was published. In 1953 Calhoun reported six additional cases satisfying the criteria which Sugar had set up.2These six cases also occurred in young males. Calhoun was interested in the relationship of Krukenberg's spindle, corneal pigmentation, and the development of glaucoma. For comparison, he studied five cases, three females and two males, with Krukenberg's spindle having no glaucoma. He used the mydriasis provocative test, the facility of aqueous outflow, and the water-drinking provocative test in order to assess the role that pigment might play in the production of glaucoma. In two males without glaucoma and with the spindle the water provocative test showed a positive result, whereas the facility of outflow