Dr. Dillenius describes a species of this order, which he found upon the tops of the mountains in Caernarvonshire in Wales; and which the inhabitants told him they used as a red dye, and found it preferable to the cork, or arcel, which they call _kenkerig_. He has intitled it, in English, _The white tartareous scarlet-dying lichenoides_[98]. He is of opinion, that this is the moss which Martin mentions, in his account of the Western Islands of Scotland, under the name of _corkir_; with which the inhabitants of the island of Sky dye a scarlet colour. They prepare it by drying, powdering it, and then steeping it for three weeks in urine. Linnæus queries whether this moss be not the same as his _lichen calcareus_[99]; a species so peculiar to limestone rocks, that where-ever that stone occurs among others, it may be distinguished at the first view by this moss growing upon it. This is a singularity which Dr. Dillenius has not mentioned in his moss: on the other hand, Linnæus does not mention any tinging property in his. The _pérèlle d’Auvergne_, or _orseille de terre_, of the French, belongs to this order of lichens, and is called by Dillenius[100] _The crayfish-eye-like lichenoides_. It is gathered in large quantities in the province of Auvergne, and is used as _orchel_; to which however it is greatly inferior. They prepare it with lime and urine; and were acquainted with its use as a dye long before the Canary weed was known[101] to them; and it is at this day in more common use than the _orchel_. We have it frequent with us upon old walls, rocks, and stones; but it is to be had in larger quantities in several other parts of Europe. The mealy tartareous _lichenoides_[102] with brown dishes, forms an article of trade with the people of West Gothland. They manufacture a beautiful red dye from it, which they sell under the name of _byttelet_[103]. Dr. Hill says we have this moss abundantly in Leicestershire and Warwickshire. The Welch make a red dye, with urine, from another moss of this order, which Dillenius describes[104] by the name of _The large leprous lichenoides with yellow plates_. These are not the only species, which are endowed with a tinging quality: other kinds have been observed to give a red or purple colour to paper in which they have occasionally been inclosed. Doubtless several would, upon sufficient trials, be found to answer equally well with the _orchel_.