The usi leaves of Samoa are obtained from Evodia horten-sis, Forst. and their aqueous infusion is used by the natives as a remedy against headache. Upon steam distillation they yield 0,09 p.c. of light brown oil with a quinone-like odor1). Its constants are: d15o0,9450; aD - 10°; nD20o1,49685; soluble in 2 vol., or more of 90 p. c. alcohol, insoluble in 20 vol. of 80 p.c. alcohol.