Persea gratissima, Gaertn., a tree indigenous to tropical America, is now cultivated everywhere in the tropics for its edible fruit known as Avocato or Agnacate. It does well as far north even as Northern Italy and Southern France. Bark and leaves contain a volatile oil having a tarragon-like odor.

Oil of the Bark

Under the designation "anise bark", Schimmel &Co. received in 1891 from Madagascar a bark1), the exterior of which resembled massoy bark, but its odor was very different. It was only later2) that its derivation from Persea gratissima was established.

The oil obtained from this bark with a yield of 3,5 p. c. was described in the first edition of this book as anise bark oil. It has an anise-like odor, but no sweet taste. d16„0,969; aD - 0°46'. In addition to small amounts of anethol, methylchavicol was found as its principal constituent, the first known natural occurrence of this substance, which had been previously prepared artificially by Eykman.

Oil of the Leaves

The leaf oil has been distilled twice: once from leaves from the botanical garden in Genoa3), and again from leaves from Cannes4). The oil, which is faintly yellowish-green and which resembles tarragon oil very closely, both as to odor and taste, had the following constants: 1.d15o607; aD + l°50'; nD18;2o,5164; 2. d16o,956; aD +22f; nD20o,51389; E.V. 3,8; E.V. after ace-tylation 18,9; soluble in 6 vol. of 80 p. c. alcohol with slight turbidity due to the separation of paraffin; soluble to a clear solution in about 1/2 vol. or of 90 p.c. alcohol.

The characteristic principal constituent of the oil is methyl-chavicol, the presence of which was established by its con1) Report of Schimmel & Co. April 1892, 53.

2) Ibidem October 1910, 19.

3) Ibidem October 1894, 69. 4) Ibidem October 1906, 59.

version into anethol and oxidation to homoanisic acid (m.p. 84 to 85°)1). The first fractions contain d-a-pinene (m.p. of nitrol benzylamine 1230)2). From the residue it was possible to separate paraffin, m.p. 53 to 54°, in silky needles by treating it with 80 p.c. alcohol.