THE LICHEN FLORA. OF THE SANTA CRUZ PENINSULA 37 



V GG. Thallus yellow. 



/. Spores simple, colorless; thallus bright lemon-color; apothe- 



cia chestnut LIII. Letharia 



II. Spores polar-bilocular, colorless; plants and apothecia 



reddish yellow or orange. 

 /. Thallus erect, lax, pendulous or decumbent; on trees and 



maritime rocks LX. Theloschistes 



JJ. Thallus short, rigid, becoming decumbent; on mari- 

 time rocks LVTII. Caloplaca 



FF. Plants gray, green, or. pale. 

 K. Apothecia present. 



L. Apothecia concolorous; thallus tufted, compressed or 

 terete,- or elongate, pendulous, and greatly compressed. 



LV. Ramalina 

 LL. Apothecia not colored like thallus. 



M. Apothecia black, pruinose or naked; thallus mar- 

 ginally fibrillose and fuzzy . .LXIV. Anaptychia 

 MM. Apothecia not pruinose or black. 



N. Apothecia chestnut; lobes long, ascendant, white 



beneath, on trees L. Cetraria 



NN. Apothecia yellowish or dusky; plants very short, 

 stout, erect, rigid, sub-crustaceous; on maritime 



rocks XLIII. Lecanora 



KK. Apothecia absent. 

 0. Lobes narrow, ascendant, margined with stout, usually 



branching fibrils LXIV. Anaptychia 



OO. Lobes not marginally fibrillose. 

 P. Sub-crustaceous; short, stout, terete; powdery, simple 

 or branched; on maritime rocks . .XLIII. Lecanora 

 PP. Thallus pendulous or erect ; more or less white sorediale ; 



on trees and shrubs LII. Everma 



j 



LICHENES. . ' 



ASCOLICHENES. 



Composed of Fungi belonging to the Ascomycetes, living .in union 

 (symbiosis ?) with Algae, these two distinct classes of plants apparently 

 forming a morphological and physiological unit. 



I. PYRENOCARPE^E: Apothecia globular, usually opening at the 

 summit by a minute pore. 



II. GYMNOCARPE^E : Apothecia more or less open and the disk 

 exposed, circular and shield-like or dish-like, elongated and variously 

 shaped, or crater-like. 



