Mace is the dried arillus of the nutmeg. It has its origin in a thickening of the funiculus extending to the outer integument of the seed near the exostome; it is therefore intermediate in nature between an arillus and arillode. As it develops and surrounds the seed it divides into branching lobes which approach one another near the apex of the seed. It is carefully separated from the seed and dried, and then forms flattened lobed pieces about 25 mm. or rather more in length, somewhat less in breadth, and about 1 mm. thick. When soaked in water and restored to its original form, it is seen to be cup-shaped. It is of a dull reddish colour, translucent and brittle. The strong and fragrant odour and aromatic taste resemble those of nutmeg.

Mace contains from 4 to 15 per cent, of volatile oil which appears to be identical in all essential particulars with that obtained from the nutmeg.

Varieties

Bombay mace (M. malabarica), considerable quantities of which are imported, is in longer, narrower pieces of dark red colour, dividing into numerous narrow lobes which are twisted together at the apex. It is devoid of aroma and valueless as a spice. The powder can be distinguished from that of genuine mace by the large amount of substances yielded to ether after exhaustion with petroleum spirit (30 per cent., as against 3.5 from genuine mace).

Macassar or Papua mace (M. argentea) is in dull, brownish fragments with a dusty surface; the lobes are few. broad and widely separated, ultimately uniting to a compact cap; the taste is distinctly acrid.