herbals from the fifteenth century onwards for lung complaints, allegedly
because it has an irregular pitted surface superficially resembling that human
organ (but that explanation could well be fanciful). Whether or not from that
source, it became highly rated as a remedy for consumption. In the New For-
est in Hampshire in the mid-nineteenth century it was still being collected
and an infusion of it extensively drunk for that ailment.^31 The plant similarly
persisted in use in the Highlands.^32 Sold today by herbalists primarily for
asthma and bladder complaints and as a bitter tonic to promote appetite, its
mucilaginous character has also made it attractive as a soothing syrup.
According to one Irish source,^33 a very common lichen in Sligo variously
known there as ‘tree lungwort’, ‘hazel rag’ or ‘crottles’ has been used locally as
a cure for piles. That sounds like a conflation of more than one kind and per-
haps refers more particularly to Parmelia species, which have been put to
related purposes.
Xanthoria parietina (Linnaeus) Th. Fries
cosmopolitan
As in the case of the mosses, there has predictably been a measure of vague-
ness in folk medicine about the kinds of lichens used, and sometimes people
can get no further than ‘a leaf called lichen which grows in mossy fields’, in the
words of one Kilkenny informant.^34 In that particular one, as it happens, the
plant in question was mentioned as boiled in milk and drunk for yellow jaun-
dice, which suggests Xanthoria parietina,a species common throughout the
British Isles which, allegedly on account of its bright yellow colour, is known
to have had a reputation for curing that ailment. In the case ofdub-cosac,on
the other hand, a lichen considered good for heart trouble in the Clare-
Galway borderland,^35 there is no such clue to its identity.
Algae
Algae comprise a variety of quite distantly related organisms that have been
recognised as belonging to a number of separate divisions. The algae included
here are Nostoc,a blue-green alga that is more closely related to bacteria, and
red, green and brown algae of the divisions Rhodophycota, Chlorophycota
and Chromophycota, respectively.
Nostoc commune Vaucher
cosmopolitan
(Folk credentials questionable) There has been a widespread European folk
Bryophytes, Lichens, Algae and Fungi 43