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usually pale brownish. P. pulvcnilenta, also brown, is dotted with 

 white particles. Parmclia frondifera (Group 6), one of the few 

 other lichens with lobed fruit-rims, has the upper surface somewhat 

 shiny. 



Pliyscia aquila. Shaggy Lichen 



Also called Anaptychia aquila. Frequent on mossy rocks and 

 tree-bases in deep woods throughout the New York area, especially 

 in limestone districts. The irregular rosette masses grow as much 

 as 10 cm. across, and often 5 mm. thick, with densely overlapping 

 parts. The long, straight branches, 1 mm. or so wide, may be hidden 

 under tiny lobes often only 0.1 mm. wide, which spring from any 

 part of the lichen, and grow in various directions, but mostly down- 

 ward, giving it a singular, shaggy, feathery appearance. In this con- 

 dition, it may be called var. detonsa. The color is grayish to tawny 

 brown when dry, pale yellowish brown in old herbarium specimens, 

 moss-green when fresh and moist, the under surface pale brownish, 

 rarely blackening, with usually pale holdfasts. 



Fruits usually plentiful, up to 5 mm. in diameter, brown or 

 blackening, with a thickish rim from which often spring prongs and 

 lobes like those on other parts of the lichen. Spores 2-celled, brown 

 or blackish, 28 to 43 by 16 to 25 microns. 



Physcia aquila is easily recognized by the small lobes with which 

 it is overgrown, and the brownish color. There is little need to dis- 

 tinguish the more densely clothed var. detonsa, as any degree of 

 this development may be found on different parts of a single speci- 

 men. The presence of these small lobes on the fruit rims distin- 

 guishes it from all other species of Physcia except P. hypoleuca, 

 pale gray, and P. pulverulenta, brown with white particles, neither 

 turning particularly green when wet, while this color change is 

 marked in P. aquila. A somewhat similar mass of small lobes is seen 

 in P armaria micro phylla (Group 10), but in this the parts are 

 smaller and shorter, growing usually close against a blue-black 

 under-crust. Parmelia frondifera (Group 6) is paler and shining, 

 with a black under surface. 



Physcia pulverulenta. Mealy Blister Lichen 



Found infrequently on mosses, trees or rocks, preferring lime- 

 stone. It may form rosettes up to 8 or 10 cm. across, with parts 3 



