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Parmelia PHYsoDES (L.) Ach. (Fig. 4.) This 

 beautiful lichen is frequently found on the 

 same dead limb of a white pine with Cetraria 

 laciinosa and C. ciliaris. It is not often 

 found in fruit, but is readily identified by its 

 smooth delicately tinted gray green thallus, 

 the lobes of which are finely cut, the margins 

 slightly curled over showing the white soredia 

 on the under side. Like the Cetrarias it is 

 loosely attached to the substratum. It often 

 grows around the small twigs of the dead 

 limbs of hemlocks, giving them a hoary ap- 

 pearance. Beneath the thallus is almost black 

 „ . , . except at the margins where it is brown and 



smooth with no ttbrils. The lobes are somewhat convex, many and deeply 

 cleft, usually overlapping each other. The apothecia, which are very rare, 

 are large, the disk is reddish brown with an entire margin. The shape of 

 the apothecium is more that of an urn than a cup. 



Parmelia coi.podes (Ach.) Nyl. (Plate VI. 2.) The thallus is flat 

 and smooth in this species, with many cleft lobes, coriaceous, glaucescent 

 in color. It is somewhat like P. physodes in appearance, but the lobes of 

 the thallus do not turn over, they are fiat and the whole effect is smoother. 

 It is found on trees and old wood, is common in the Eastern and Southern 

 States. 



Fig. 4. P. p/tysodcs. 



Parmelia gi.tvacea 

 (L.)Ach. (Fig. 5.) As the 

 specific name indicates 

 this lichen is olive in 

 color. When young it 

 is a light olive, but grows 

 darker as it develops, 

 and is finally an olive 

 brown. The lobes are 

 fiat and rounded, grow- 

 ing much like /'. capera- 

 tci, except that they ad- 

 here closely to the sub- 

 stratum. Often the up- 

 Fig. 5. /'. olivacea. per part of the thallus 



is covered with isidioid granules. Apothecia are frequent and are dark 

 brown with wrinkled margins. Beneath, the thallus is black with fine fibrils. 

 /'. olii'acea grows on trees and is difficult to collect unless a part of the bark 

 is taken. When scraped off and examined with a hand lens the lower corti- 

 cal layer is seen to be very tliin, the woolly medullary layer showing dis- 

 tinctly. 



