“…and e) physiological. The results of Lilienfeld (1929), Demerec (1932), Imai (1934), Malinowski (1935), Sirks (1950), Tanaka (1951Tanaka ( , 1954Tanaka ( , 1959Tanaka ( , 1961Tanaka ( , 1962, Lindegren (1953Lindegren ( , 1956, Hazelwood et al (1955), Shif riss (1955), Brink (1956Brink ( , 1958, Zamenhof et al (1956Zamenhof et al ( , 1958, Ishikawa (1957), Smith et al (1957), Sand (1957), Sand et al (1960), Lewis (1958), Schwarts (1958, Moav et al (1960), Sand (1957), Sand et al (1960), Sandler et al (1960, Moav (1961), Nagai (1962), Babos et al (1962), Scholtissek (1962), Barnett et al (1963), Dawson (1964), Frydenberg (1964, Grigg (1965), Alderson (1966), Alderson et al (1966), Darlington (1966), Nasim (1966), Ryasty (1966), and Fincham et al (1967) seem to be due to genic instability.…”