PHYSCIA. 67 



X. PHYSCIA (DC., Fr.) Th. Fr. 



Apothecia scutellseform j the disk thickish ; the hypo- 

 thecium colourless. Spores ellipsoid, biloeular (or, more 

 rarely, ID exotic species, 4-plurilocular) brown. Spermatia 

 ellipsoid, or, mostly, oblong, on multi-articulate sterigmas j 

 or, very rarely (n. 9) acicular, on sub-simple sterigmas. 

 Thallus foliaceous, ratnoso-laciniate, stellate, or now ascend- 

 ant and Everuiseform, sub-cartilagineous j more or less fibril- 

 lose, or rarely naked, beneath. For the anatomy of the 



thallus see Schwendeuer Unters. I. c. 2, 161, and 3, 154-7. 

 From Physcia proper (typified by P. stellaris) in which the 

 cortical layer is parencbymatous, and thus distinguishable 

 from the confused tissue which constitutes the same layer 

 in Parmelidj certain ascendant species (typified by P. ciliaris, 

 but including also P. speciosa) vary in exhibiting a more 

 properly filamentous cortical layer : these differences finding 

 however a degree of reconciliation, as shewn by Nylander, 

 within the range of modifications of P. pulverulenta. 



* Hagenia (Eschiv.) Fr. Cortical layer of intertangled fila- 

 ments with a mostly longitudinal direction ; thallus beneath often 

 ecorticate. 



1. P. erinacea (Ach.) Tuckerm. j thallus cartilagineous, dif- 

 fusely caespitose, naked, glaucous-white ; beneath ecorticate and 

 very white ; the ascendant, flexuous lobes irregularly torn-cleft, 

 flattish, ciliate with long fibrils ; apothecia smallish, scattered, 

 pedicellate, the blackish -brown disk soon tumid, repressing the 



entire margin. Spores biloeular, ^^ mic. Obs. Lich. I. c. 4, 



p. 388. Borrera, Ach. L. U. p. 499 ;" Syn. p. 222. P. ciliaris, var., 

 Nijl. Syn. I, p. 414. 



On shrubs, sea coast of California (Menzies) Ach. L. U. 1810; 

 and later collectors. The thallus of this, of P. comosa, and 

 of P. hispida are externally much alike when young. 



2. P. speciosa (Wulf., Ach.) Nyl. ; thallus cartilagineous- 

 membranaceous, loosely stellate, appressed, greenish-glaucous ; 

 beneath corticate, whitish, with fibrils of the same colour ; lobes 

 sinuately pinnatifid, flat, obtuse, with more or less ascendant, 

 powdery edges; apothecia smallish to middling- sized, sub- 



