string: Trivedi, Mehta, and Nanavaty (1966) reported a case of their own and reviewed the literature of the previous 15 cases, and since then further cases have been described by Bateson, Hayes, and Woo-Ming (1968), Gautam (1969), and Pound and Willis (1969). Apart from this last case, which occurred in an infant, the age of presentation has varied from 16 to 66 years.