128 



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Hab. Arboribus, in plaga occidentali Americas septentrion- 

 alis. Menzies. Douglas. Scouler. 



Thalbis suborbicularis-t expansus, stellatim ramosusj laciniis 

 compactis, flexuosis vix imbricatis dichotome divisis, 

 ubique inflatis, fistulosis, apicibus liberis, obtusis. Color 

 superne pallide albo-virescens, apicibus fuscescentibus, 

 nunc minute nigro-punctatus, subtus aterrimus^ nitidus, 

 intus etiam nigen Apothecia magna, conspicua, fere 6 

 lineas lata, superne disco concava flavo-fusca, margine 

 elevata, inflexa, demum lacerata, subtus in stipitem fis- 

 . tulosum attenuata, ita ut totum apothecium infundibuli- 

 forme. 



This very singular species of Parmelia has hitherto only 

 been described by Acharius from specimens gathered by Mr. 

 Menzies, but destitute of fructification. I possess the plant, 

 however, from Mr. Menzies and from Mr. Douglas and Dr. 

 Scouler, abounding in apothecia, and am thus enabled 

 to give a perfect figure, from which it will be seen how 

 much it differs in its structure from all the other Icnown 

 lichens, having its ramifications everywhere hollow and 

 inflated, the colour on the underside and within a deep 



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and shining black, and the apothecia tapering down at their 

 base into a hollowed stipes or stalk; thus making the fruc- 

 tifications infundibuliform. 



X 



Fig. 1, Portion of a lacinia ; and Jig. 2, Section of an apo- 

 thecium : — vfiagnijied. 



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