PAKMELIACE^E. 





] 



PATELLIXA. 



PARMELIA'CE^E. A family of open- 

 fruited Lichenaceous Lichens, bearing ses- 

 sile shields, the borders of which are formed 

 by the surface of the thallus. This family 

 corresponds nearly to the series Bamalodei, 

 Phyllodei, and Placodei, of the family Li- 

 chenacei in Leighton's Brit. Lich. Flora. 



British Genera. 



* Apothecia at first veiled, thallus horizontal : 

 Peltigeri. 



Peltiyera. Thallus foliaceous, leathery 

 or membranous, spreading, lobed, witn 

 woolly veins beneath. Apothecia somewhat 

 circular, adnate on the upper side of the 

 lobules of the thallus, with a border formed 

 by this. 



Nephroma. Thallus foliaceous, leathery 

 or membranous, spreading, lobed, naked or 

 hairy beneath. Apothecia circular or reni- 

 form, adnate on the underside of the lobules 

 of the thallus, with a border formed by the 

 latter. 



Solorina. Thallus leathery, membrana- 

 ceous, veined or fibrillose oelow. Apo- 

 thecium suborbicular, affixed to the upper 

 surface of the central lobes of the thallus ; 

 veil finally forming an evanescent margin. 



** Apothecia at first closed, thallus horizontal : 

 Euparmeliacei. 



Sticta. Thallus foliaceous, leathery-car- 

 tilaginous, spreading, lobed, free and downy 

 beneath, with little cavities or hollow spots, 

 often containing a powdeiy substance. Apo- 

 thecia beneath formed of the thallus, to 

 which they are appressed and fixed by a 

 central point, the disk coloured, flat, sur- 

 rounded by an elevated thalline border. 



Parmelia. Thallus foliaceous, membranous 

 or leathery, spreading, lobed and stellated 

 or laciniated, more or less fibrous beneath. 

 Apothecia circular, formed by the thallus, 

 fixed by a central point, disk concave, 

 coloured, with an inflexed margin from 

 the thallus. 



Urceolaria. Thallus uniform, crusta- 

 ceous. Apothecia urceolate, somewhat im- 

 mersed, the thalline border somewhat di- 

 stinct. 



Lecanora. Thallus crustaceous, spread- 

 ing, flat, adnate and uniform. Apothecia 

 circular, thick, sessile and adnate; disk 

 plano-convex, the border thickish, formed 

 of the crust, and of the same colour. 



Physcia. Thallus cartilaginous, branched 

 and laciniated, the segments free, generally 

 grooved beneath, the margins frequently 



cili ated . Apothecia circ ular, peltate, formed 

 of the thallus, the disk coloured and sur- 

 rounded by an inflexed thalline margin. 



*** Apothecia open from the first, thallus 

 mostly centripetal, vertical or sarmen- 

 tose, without any In/pothalhts : Usnei. 



Cetraria. Thallus foliaceous, cartila- 

 gineo-membranous, ascending or spreading, 

 lobed and laciniated, smooth and naked on 

 both sides. Apothecia circular, obliquely 

 adnate to the margin of the thallus, the 

 lower portion being free (from the thai] us) : 

 disk coloured, plano-concave, with an in- 

 flexed thalline border. 



Roccella. Thallus cartilaginous, leatb TV. 

 rounded or flat, branched or laciniate. 

 Apothecia circular, adnate to the thallus, 

 disk coloured, plano-convex, with a thalline 

 border, at length thickened and elevated, 

 and covering a black powder concealed 

 within the substance of the thallus. 



Ramalina. Thallus cartilaginous, gene- 

 rally branched and laciniated, somewhat 

 shrubby, generally bearing powdery wnrls. 

 cottony and compact within. Apothecia 

 circular, shield-shaped, stalked and peltate, 

 flat, bordered, entirely formed of the sub- 

 stance of the thallus, and mostly of the 

 same colour. 



Cornicularia. Thallus cartilaginous, 

 branched, subcylindrical, fistulose, or nearly 

 solid and cottony within. Apothecia cir- 

 cular, terminal, obliquely peltate, entirely 

 formed of the substance of the thallus, at 

 length convex, more or less bordered and 

 often toothed. 



Evernia. Thallus somewhat crustaceous, 

 branched and laciniated, angled or com- 

 pressed, cottony within. Apothecia circular, 

 shield-shaped, sessile, with the disk concave, 

 coloured, and an inflexed border formed by 

 the thallus. 



Ustwa. Thallus somewhat crustaceous, 

 rounded branched, generally pendulous, 

 with a central thread. Apothecia circular, 

 terminal on processes of the thallus, peltate, 

 nearlv of the same colour, mostly without a 

 raised border, but ciliated at the margins. 



BIBL. See the genera. 



PASTE, EELS IN. See ANGUILLULA. 



PATELLI'NA, Will. A genus of Hya- 

 line Foraminifera, of the Eotaline family. 



Trochoid, formed of a low cone of sub- 

 _ spiral, semiannular, and annular chambers, 

 divided into chamberlets. Sometimes in- 

 crusted with small cells externally, and 



