“…(3) There is hemeralopia and the dark adaptation curve is monophasic and high [Saebö, 1948;François et al, 1960;Kurstjens, 19651. (4) There is acquired dyschromatopsia, which may be of the red-green axis [ V er riest, 1962], (5) The electroretinogram may be nor mal in the initial stage, but afterwards it deteriorates progressively and becomes ex tinguished [Bounds, 1954;François et al, 1956;Franceschetti and Dieterle, 1957;Kurstjens, 1965;Schäfer and Tenner, 1970], It seems that the scotopic components dis appear more rapidly than the photopic com ponents [Kurstjens, 1965;Schäfer and Ten ner, 1970], (6) The electro-oculogram is also serious ly pathologic [Krill and Archer, 1971). It is mostly extinguished [Kurstjens, 1965;Schmidt and Straub, 1970).…”