Mosses and Lichens 



ammonia or limewater. For this reason it serves as a test for 

 acid and alkaline substances. 



LICHENS AS DRUGS 



Since many lichens had a fancied resemblance to certain parts 

 of the human body, they were supposed to be a cure for the 

 disease of that part of the body which they resembled. Old 

 Man's Beard (Usnea barbata, Colour Plate 1) was used to 

 promote the growth of hair. Yellow wall lichen (Xanthoria 

 parietina, Colour Plate II) was given for jaundice. 



Peltigera canina dried and finely powdered and mixed with red 

 pepper formed an anti-hydrophobia powder ( Pulvis antilyssus) 

 of the London Pharmacopoeia. In the history of the Royal 

 Society it is recorded that several mad dogs belonging to the 

 Duke of York were saved by this powder. 



A prescription of Dr. Mead reads: "Patient is bled and 

 ordered to take a dose of peltigera in warm milk for four conse- 

 cutive mornings thereafter. He must take a cold bath every 

 morning for a month, and for two weeks subsequent, a bath 

 three times a week." 



LICHENS AS FOOD 



" Iceland moss' ' (Cetraria Islandica, Colour Plate VII) is even 

 now used as an article of food, as it contains a high per cent, of 

 lichen-starch. 



The Spotted Lungwort (Sticta pulmonan'a, Colour Plate VII) 

 was considered a sure cure for lung trouble and "was used in a 

 Siberian monastery for a beer which was noted for its peculiar 

 bitterness. 



The manna of the Israelites is supposed to have been a species 

 of Lecanora (Lecanora esculenta). This lichen is plentiful in 

 Algeria and Tartary, as well as in mountainous districts of other 

 countries. It is its habit to grow and spread rapidly and, as it is 

 loosely attached, it is often carried by the wind down the sides 

 of mountains into the valley, where it is spoken of as " Rains of 

 manna." Kirghiz Tartars eat it as "earth bread." 



It first forms thick-wrinkled and warted grayish-yellow crusts 

 on the stones. Within, they are as white as parched corn. 



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