LICHENES 



451 



2. E. flu vKitile, DC. [River} : Thallus cartilagineous-mem- 

 branaceous, flaccid, lobed, green, becoming fuscescent when dry , 

 lobes rounded, auriculate-lobulate ; under side naked, reticulate- 

 rugulose, pale fuscous becoming black ; ostioles rather prominent, 

 black. 



Hob. On wet and frequently inundated rocks. 



3. E. pus 1 11 11 III, Hedw. [Little] : Thallus cartilagineous, 

 squamulose-foliaceous, smooth, brownish-olivaceous, pale on the 

 under side, arising from a black fibrillose hypothallus; ostioles 

 black, somewhat prominent, pertuse. 



Hob. On naked clays ; Newlin Barrens : very rare. 



4. E. arbftrcuni, Schweinitz, MS. [Tree]: Thallus squamulose, 

 foliaceous, subcoriaceous, from glaucous becoming fuscous ; scales 

 closely imbricate, often concave, black and downy beneath ; ostioles 

 black, scarcely prominent. 



Hob. On trunks, &c. 



Obs. An extremely rare species. I have only once found it, on 

 the detached bark of an old black-oak stump. 



60S. PERTITSA^RIA, DC. 



[Latin, pertusus, punched, or bored through ; descriptive of the plant.] 

 Apothecia verrucaeform, formed from the thallus, including naked 

 waxy-gelatinous colored nuclei. Thallus crustaceous, often passing 

 into soredia and isidia. 



1. P. pertusa, Ach. [Perforate] : Crust cartilagineous, glaucous- 

 white; apothecia depressed-hemispherical, irregular; ostioles de- 

 pressed, discrete, the perfect ones black-papillate. 



Far. a. sorediifera, Fr. crust sterile, sorediiferous. 



Far. b. areoldta, Fr. crust thicker, rimose-areolate, often sterile and soredi- 

 iferous. 



Fur. c. leucostoma, Fr. ostioles white, the black papillae being deficient. 

 Hob. On trunks ; sometimes on stones : frequent. 



2. P. faginea, Tuckerm. [Beech]: Crust tartareous-cartila- 

 gineous, cinereous-white, the circumference zonate, often thin, 

 polished, bluish ; apothecia hemispherical, bursting into mealy 

 eoredia. 



Far. b. orbiculata, Tuckerm. apothecia explanate; nuclei expanded into asub- 

 membranaceous denudate flesh-colored disk. 

 Hob. On trunks, rails, and rocks: common. 



3. P. globulari 1 Ach. [Globular]: Cnist of very numerous 

 eubglobose, and ramulose, glaucescent granules ; apothecia (in- 

 frequent) globose, smooth, with a solitary impressed punctiform 

 black ostiole. 



Hab. On Mosses, &c. : rare. 



TRIBE 2. VERRUCARIA X CEAE. 



Apothecia rounded, a closed proper exciple (perithecium) becoming pertuse with an 

 t>stiole, or at length open; nucleus gelatinous, subhyaline, deliquescent; thallus 

 cnutaceous. 



