The Probert Encyclopaedia of Nature

ARIL

Aril or aririus, in some plants, as in the nutmeg, is an extra covering of the seed, outside of the true seed-coats, proceeding from the placenta, partially investing the seed, and falling off spontaneously. It is either succulent or cartilaginous, coloured, elastic, rough, or knotted. In the nutmeg it is known as mace.
Research Aril