4 i8 ECONOMIC AND TECHNICAL 



//. LICHEN COLOURS AND SPECTRUM CHARACTERS. In a comparative 

 study of vegetable colouring substances, Sorby 1 extracted yellow colouring 

 matters from various plants distinguished by certain spectrum characters. 

 He called them the "lichenoxanthine group" because, as he explains, "these 

 xanthines occur in a more marked manner in lichens than in plants having 

 true leaves and fronds. Orange lichenoxanthine he found in Peltigera 

 canina, Platysma glaucum, etc., when growing well exposed to the sun. 

 Lichenoxanthine he obtained from the fungus Clavaria fusiformis ; it 

 was difficult to separate from orange lichenoxanthine. Yet another, which 

 he terms yellow lichenoxanthine, he obtained most readily from Physcia 

 (Xanthorid) parietina. The solutions of these substances vary according to 

 Sorby in giving a slightly different kind of spectrum. He did not experi- 

 ment on their dyeing properties. 



F. LICHENS IN PERFUMERY 



a. LICHENS AS PERFUMES. There are a few lichens that find a place 

 in Gerard's 2 Herball and that are praised by him as being serviceable to 

 man. Among others he writes of a " Moss that partakes of the bark of 

 which it is engendered. It is to be used in compositions which serve for 

 sweet perfumes and that take away wearisomeness." At a much later date 

 we find Amoreux 3 recording the fact that Lichen (Evernia) prunastri, 

 known as " Mousse de Chene," was used as a perfume plant. 



Though lichens are not parasitic, the idea that they owed something of 

 their quality to the substratum was firmly held by the old herbalists. It 

 appears again and again in the descriptions of medicinal lichens, and still 

 persists in this matter of perfumes. Hue 4 states in some notes to a larger 

 work, that French perfumers extract an excellent perfume from Evernia 

 prunastri (Fig. 59) known as "Mousse des Chenes" (Oak moss), and it ap- 

 pears that the plants which grow on oak contain more perfume than those 

 which live on other trees. The collectors often gather along with Evernia 

 prunastri other species such as Rainalina calicaris and R. fraxinea, but these 

 possess little if any scent. A still finer perfume is extracted 5 from Lobaria 

 puhnonaria called " moss from the base of the oaks," but as it is a rarer 

 lichen than Evernia it is less used. Most of the Stictaceae, to which family 

 Lobaria belongs, have a somewhat disagreeable odour, but this one forms 

 a remarkable exception, which can be tested by macerating the thallus and 

 soaking it in spirit : it will then be found to exhale a pleasant and very 

 persistent scent. These lichens are not, however, used alone; they are com- 

 bined with other substances in the composition of much appreciated perfumes. 

 The thallus possesses also the power of retaining scent and, for this reason, 

 lichens frequently form an ingredient of potpourri. 

 1 Sorby 1873. 2 Gerard 1597. 3 Amoreux 1787. 4 Hue 1889. 5 Hue 1900. 



