This section is from the book "The Gardener's Monthly And Horticulturist V23", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
It is generally supposed to be a sport from Adiantum scutum. I cannot at present remember whether I have ever written to raise the question in the Journal of Horticulture whether it is not really the barren form of Adiantum scutum. The original plant was found in a sugar plantation belonging to a Mr. Farley either in Jamaica or Barbadoes, I believe, but I am speaking without notes before me. I remember one of the first, if not the first, plant in England belonged to a cousin of mine, Mr. Miles at Marlborough, and I once saw decided fertile fronds on a plant which was identical with scutum. Several seedlings were raised by Messrs. Veitch, of Exeter, from spores of this or other fertile fronds, but they always reverted to scutum. Many ferns have both fertile and barren fronds on the same plants - take Blech-num boreale, for instance, and Pteris. What I wish to ask fern-growers is, have they ever seen any true plants of Adiantum Farleyense with spores on the back of the fronds, and have they ever seen barren fronds on Adiantum scutum? - Cor. of Journal of Horticulture.