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POPULAR HISTORY OF LICHENS. 



a leprose, amorphous mass of the character which we have 

 already described as that of the old genus Lepraria (var. 

 viridis, E.B. 2148). The apothecia have sometimes more 

 or less of a red tint, their margin disappears, they become 

 irregular in form, and often confluent or closely crowded 

 (E. B. 1795) ; at other times they are of very minute size, 

 though very numerous. One variety, Candelaria, — so called 

 from being used by the Swedes to dye the candles set apart 

 for their religious ceremonies, — has lately been transposed 

 by Massolongo into a separate genus {Candelaria vulgaris). 

 It is microphylline, lacerate- dissected, and the margin of 

 the apothecia granulose-pulverulent. On moist and shady 

 parts of walls, frequently covered or intermixed with cob- 

 webs and dust, we have noticed a white-variegated con- 

 dition of the thallus ; this will be found on inspection to 

 be due to the partial destruction, probably by insects, of 

 the cortical layer and of the surface of the apothecia, there- 

 by exposing the subjacent white, cottony, medullary layer. 

 There is a double cortical layer, — the superior yellow, and 

 consisting of thick-walled cellules closely aggregated ; the in- 

 ferior white, composed of similar cell-elements, more hygro- 

 metric, and giving off numerous filamentous fixuree from its 

 under-surface. The paraphyses are linear, claviform, com- 



