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Cetraria hiascens. Cleft Lichen. 



Mentioned doubtfully, as it is not likely to be found within 

 the area, but may grow under the same conditions as C. 

 islandica. Its hue is paler brown or straw-color, and the manner 

 of branching less complicated, but the distinguishing feature is 

 seen in the tips, which, unlike the blunt branches of C. islandica, 

 split into many fine, pointed divisions, giving an appearance 

 more like the Reindeer Mosses (Group 2), but easily distin- 

 guished because the stalks are flat, and not hollow. As the 

 under surface, though structurally different from the upper, 

 does not appear so, it could be confused with Ramalina calicaris 

 (Group 3), except for the fact that it grows on the ground, the 

 Ramalina on trees. 



The species of Cetraria (Shield Lichen) which follow are 

 often not actually stalked, but rise from their holdfasts by folds 

 and wrinkles of their papery lobes, and are therefore closely 

 akin to thePapery Lichens. Still other species of Cetraria which 

 do not rise much above the foothold, will be found under 

 Papery Lichens in Group 5, with Parmelia (also Shield 

 Lichen). Though it is not always easy to differentiate these 

 two kinds of Shield Lichen, Cetraria tends to raise its margins 

 at least from the foothold, while Parmelia tends to lie more 

 flat against it. The fruits of Cetraria spring from the edge of 

 the lobe, while those of Parmelia lie on the upper surface, 

 usually toward the center. Cetraria fruits have usually toothed 

 or warty rims, while the rims in Parmelia are nearly always 

 smooth. Both Cetraria and Parmelia have small, undivided, 

 colorless spores, which distinguish them from most other 

 Papery Lichens, Sticta, Peltigera, Nephroma, Solorina (Group 

 7), Physcia (Group 8), Teloschistes, Caloplaca (Group 9), Col- 

 lema (Group 11). 



Cetraria juniperina. Cedar Lichen. 



Also called C. viridis. A frequent lichen in the pine barrens, 

 and seen around upland bogs and ridges, growing on twigs and 

 bark of White Cedar, or on other trees and wood. It forms a 

 tuft of considerably divided papery lobes, wrinkled, pitted, 

 veined, and the margins waved and crinkled. It will spread 5 

 cm. or more across, and rise 1 or 2 cm. from the foothold. The 

 color may be olive green when wet, or yellow to greenish gray 



