Today’s photograph was taken on a January visit two years ago to the impressive Ferns Conservatory at the Montréal Botanical Garden, Canada’s largest botanical garden. The scanned illustration (and the accompanying text in the first comment below) are from a public domain work by Sir William Jackson Hooker, Garden ferns; Or, Coloured figures and descriptions: with the needful analyses of the fructification and venation, of a selection of exotic ferns adapted for cultivation in the garden, hothouse, and conservatory. This book was digitized by Google and can be downloaded in its entirety as a PDF or viewed online.
Adiantum is broadly distributed worldwide, with centres of diversity in Andean South America and eastern Asia. Representatives of the genus are also found in North America (Adiantum aleuticum), Europe, Africa, Australia and New Zealand.
It is difficult to find much information online about this particular species. Native from Venezuela to Peru, Adiantum polyphyllum was scientifically described and published in 1810 by the German botanist Carl Willdenow. However, the specimens he described were likely collected by the “founder” of biogeography and plant explorer, Alexander von Humboldt. For an excellent overview on the topic of ferns and biogeography, see: Barrington, D. 1993. Ecological and Historical Factors in Fern Biogeography. Journal of Biogeography. 20(3): 275-27. (might be a restricted-access link).
Known commonly, perhaps, as either giant maidenhair or many-leaved adiantum, Adiantum polyphyllum is a sizable fern (see this photograph), with a stipe to perhaps 0.6m (2ft) in height and fronds reaching an additional 1m (3ft) in length. I was struck, as Hooker describes it, by the “intensely ebeneous-black stipites and rachises”.