Mosses and Lichens 



upon this lichen, and in times when food has been scarce, even 



man has been glad to avail himself of it. 



In Sweden at one time the people made their bread 

 from this lowly plant. 



In moist places, velvety green ruffles 

 (Pdtigera, Colour Plate VII) spread on 

 the ground or on stones and stumps, 

 the edges of the ruffles set with fruit- 

 disks curled in such a way as to resem- 

 ble brown finger nails, or dogs' teeth. 

 In the days when drugs were selected 

 because of a fancied resemblance to the 

 part of the body in need of cure, Pelti- 

 gera canina was considered a cure for 

 Section hydrophobia and received its specific 



ot thaiius toshow aig* and hyp- name canina because of the resemblance 



hae in definite layers. 



of its fruit-disks to a dog's teeth. When 



dry the surface of the ruffles is a light quaker-drab, which quickly 

 changes to a bright green when the lichen is damp. 



It is on the bark of trees that one finds the richest har- 

 vest of lichens. They are found in the greatest profusion 

 on the north sides of -^ 



the trees and for this 

 reason serve the wood- 

 man as a guide through 

 the forest. Emerson in 

 "Wood Notes" refers 

 to this, when he says: 



" The moss upon the for- 

 est bark 

 Was pole-star when the 



night was dark." 

 (Colour Plate IX) 



The encrusted lichens, 

 Parmelia (Colour Plate 

 V), and Stic fa (Colour 

 Plate VII) which grow flat on rocks and trees, cling so closeiy 

 that they can with difficulty be separated. Their pretty gray or 

 green mats dotted with shining brown fruits grow from the 

 centre outward in an ever-widening circle, covering old fence 



28 



Epkebe Kerneri. A gelatinous lichen with the alga 

 distributed throughout the thallus. 



