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ing far up the boles and over the larger Ixnighs. You can see them 

 j)lainly from a i)assing car. The radiating branches and lobes, 

 usually about 1 cm. wide, lie fairly close to the foothold, especially 

 at their tips, but crowd each other into ridges and mounds often 

 1 cm. high. The tips spuead out as much as 2 cm. wide, shallowly 

 lobed and with scalloped margins. The pale yellowish upper sur- 

 face is not quite shining, but rather of the texture of kid leather. 

 Older parts darken to yellowish gray or grayish olive, often over- 

 spread with pale, new tips from another direction. Besides the 

 larger wrinkles, this lichen has small ones, about 2 to the mm., 

 beginning a little back from the tips and flowing with the direction 

 of growth, or again spreading irregularly and crossing each other. 

 The higher ridges may break into warts dusted with yellowish 

 soredia. The under surface is black with very short black holdfasts, 

 but at the tips becomes shiny brown, without holdfasts, or with 

 the holdfasts reduced to dots. 



Fruits are very rare, up to 12 mm. across, saucer-shape, chest- 

 nut-brown, with a wavy and often warty rim. Spores undivided, 

 colorless. 13 to 20 by 7 to 10 microns. 



The same tree will often show Pannelia capcrata and P. rudccta, 

 with their contrasted shades of pale yellow and pale blue-gray. 

 This difference in color is usually sufficient distinction, but P. ru- 

 decta, for further contrast, has white dots scattered over the 

 upper surface, and a pale drab under surface. Small specimens 

 might be confused with P. tiliacea var. isidioidea, which, however, 

 is always blue-gray or blue-green. Sticta aiuplissiina (Group 7), 

 an infrequent lichen in the Xew York area, forms very large, 

 somewhat similar rosettes, which are pinkish gray with many light 

 red fruits, and turn deep grass-green when wet. If on rocks, 

 P. capcrata must be separated from P. conspcrsa, of similar color, 

 by its wider, less shining tips. 1)}- its black under surface, and by 

 its small, rather regular wrinkles. Few other lichens reach com- 

 parable size. Sticta pidnionaria (Group 7) is pale brownish both 

 above and beneath, and deeply pitted. Paniiclia pcrlata. P. per- 

 forata and their subspecies have tips which rise 1 cm. or more 

 from the foothold, and none are yellow except the rare P. sul- 

 phurata, which is sulphur colored also within, as seen when broken, 

 and probably not found in the Xew York area. (P. capcrata is 

 white within.) The yellow of P. capcrata, which is very pale, must 



