page_title: Fern
section_title: Pteridomania
hierarchical_section_title: Fern / Culture / Pteridomania
caption_attribution_description: English: Barnsley's fern illustrates the use of affine translations in an iterated function system (IFS) to create a fractal. In Table III.3 of Michael Barnsley's book, the IFS code for the four affine transformations for the Barnsley leaf is given as a table of values for the coefficients a, b, c, and d, the constants e and f and the probability percentage factor of p as follows: a b c d e f p 0 0 0 .16 0 0 .01 .85 .04 -.04 .85 0 1.6 .85 .2 -.26 .23 .22 0 1.6 .07 -.15 .28 .26 .24 0 .44 .07
context_page_description: A fern is a member of a group of vascular plants that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissues that conduct water and nutrients and in having life cycles in which the sporophyte is the dominant phase. Ferns have complex leaves called megaphylls, that are more complex than the microphylls of clubmosses. Most ferns are leptosporangiate ferns. They produce coiled fiddleheads that uncoil and expand into fronds. The group includes about 10,560 known extant species. Ferns are defined here in the broad sense, being all of the Polypodiopsida, comprising both the leptosporangiate and eusporangiate ferns, the latter group including horsetails or scouring rushes, whisk ferns, marattioid ferns, and ophioglossoid ferns.
  Ferns first appear in the fossil record about 360 million years ago in the middle Devonian period, but many of the current families and species did not appear until roughly 145 million years ago in the early Cretaceous, after flowering plants came to dominate many environments.
context_section_description: Pteridomania is a term for the Victorian era craze of fern collecting and fern motifs in decorative art including pottery, glass, metals, textiles, wood, printed paper, and sculpture "appearing on everything from christening presents to gravestones and memorials." The fashion for growing ferns indoors led to the development of the Wardian case, a glazed cabinet that would exclude air pollutants and maintain the necessary humidity.
  The dried form of ferns was also used in other arts, being used as a stencil or directly inked for use in a design. The botanical work, The Ferns of Great Britain and Ireland, is a notable example of this type of nature printing. The process, patented by the artist and publisher Henry Bradbury, impressed a specimen on to a soft lead plate. The first publication to demonstrate this was Alois Auer's The Discovery of the Nature Printing-Process.
  Fern bars were popular in America in the 1970s and 80s.
caption: Barnsley fern created using chaos game, through an Iterated function system (IFS).
exif: {}