434 THALLOPHYTES 



2. E. furfurftcea, Mann. [Scurfy'] : Thallus laciniate-foliace- 

 ous, linear, dichotomous, channelled and becoming black beneath ; 

 apothecia pedicellate ; disk rufescent. 

 Hob. Old fences, Ac. rather rare. Mostly sterile. 



Obs. Sometimes remarkably cinereous-furfuraceous. 



593. RAHALIWA, Ach. 



[Latin, Ifamcde, a dead branrh ; from a fancied resemblance.] 

 Apothecia scutellaeform, thick, pedicellate-subpeltate, open, scat- 

 tered above and beneath; disk open, placed upon the gonimous layer. 

 Thallus erect-spreading, ramose-laeiniate, of the same substance and 

 color throughout. 



1. R. C'SUiniris, FT. [Cup-like]: Thallus ramose-foliaceous, 

 cartilagineous, rigescent, lacuno'-e, glaucous ; apothecia plane with 

 an elevated margin, pale. The following vars. occur: 



Var. &.fraxinea, Fr. laciuiae long, expanded; apoth' % cia lateral. 



Var. To.fastigiata. Fr. laciniae shorter, fasligiato; apolheda subterminal. 



Var. c. canaliculata, Fr. laciniae linear, attenuated, channelled beneath; apoth- 

 cia subterminal. 



Var. a. farinacea, Schaer. laciniae linear-attenuate, rugose-lacunose, sorediifer- 

 ous ; apothecia scattered. 

 Hob. On trunks of trees ; fences, &c. : common. 



2. R. polymorplia, Ach. [Many-form]: Cespitose; thallus 

 cartilagineous, rigid, longitudinally costatc-rugose, glaucous, often 

 sorediiferous and the soredia termin; tl-capituliform ; apothecia sub- 

 terminal, margin elevated, disk pale. 



Sab. On rocks; Buck Run: rare. Smaller than the preceding. 



594. CETRA V RIA, Ach. 



[Latin, Cktra, an ancient buckler; from the form <>f the apothecia.] 

 Apothecia scutellale, subpcltate, seated obliquely on the apices of 

 the thallus. Thallus cartilagineous-nicmbranaceous, ascendant, 

 smooth beneath; lobes subt<:rcte, or foliaceous and somewhat con- 

 cave above. 



JB^F" Thallus coriaccous-membranaceous. 



1, C. glattca, Ach. [Glaucous]: Thallus membranaceous, 

 foliaceous, sinuate-lobed, ascendant, glaucous, becoming black 

 the under side ; apothecia dark reddish-chestnut. 



Var. b. sterilis, Fr. laciniae short, broad, rather deprc**ed, fuscous-black beneatl 

 Hob. On trunks of trees; fences, &c.: common. The var. only has yet been fbun 



2, C. C'iliiiris, Ach. [Fringed']: Thallus foliaccoas, rcticulat 

 lacunose, glaucous-green passing to fuscous ; under side whitish 

 fuscescent; lobes crisped, oil iate, or black-denticulate; apotheci 

 elevated, crenate, dark-fuscous. 



Hob. On trees, and fences : common. 



3, C. lactmusa, Ach. [Pitted"] : Thallus cnrtilagineous-cor 

 aceous, foliaceous, round-lobed, rugose or reticulate-cellulose, glai; 

 cescent, under side whitish, or spotted with white ; lobes crenatt 

 crisped, black-denticulate ; apothecia elevated, large, entire, dar 

 reddish. 



