64 HERRE 



Thallus fruticose, tufted and shrub-like, erect, branched, terete, 

 smooth, with short, fine, and very numerous terminal branchlets, 

 these often in clumps which shatter off very readily; color silvery 

 gray or whitish, but varying to brownish or a decided brown; rarely 

 reddish. AUke on all sides; KOH — . Medullary layer densely 

 cottony; violet with I. 



Apothecia terminal, within the swollen and globular tips of the 

 fertile branches, which split open, exposing the globose apothecia; 

 spores violet-black, simple, spherical, 7 — lo /< in diameter. 



On trees, dead wood, and sandstone. On the Pacific side of the 

 peninsula occurring from near sea-level to the summit of the range, 

 but not descending on the Bay side more than a few hundred feet, 

 remaining within the limits of the redwood and spruce forests. 

 Occasionally found in great abundance. A strikingly handsome 

 plant. Described from Europe and recorded from Arctic and cool 

 temperate America, Madeira, and Australasia. 



GRAPHIDINEiE. 



Thallus crustaceous, uniform, without cortex or with a cortex on 

 the upper side; or fruticose, erect or decumbent, with an evident 

 cortex and medulla; alga Palmella, Trentepohlia, Phycopeltis or Phyl- 

 laclidium. 



Apothecia compressed, more or less linear, with small, fissure-like 

 disk, are characteristic of the group. Proper margin well developed 

 or absent; sometimes with a thalline margin; innate or sessile, rarely 

 on a short stipe. Spores colorless or dark, variously shaped, but 

 more often spindle or needle-shaped, and multi- or murilocular. 



KEY TO FAMILIES. 



A. Apothecia without margin ArthoniacecB 



A A. Apothecia with margin. 

 B. Thallus crustaceous. 



C. Without cortex GraphidiacecB 



CC. Cortex present on upper side DirmacecB 



BB. Thallus fruticose, erect or decumbent Roccellacem 



ARTHONIACEiE. 



Thallus uniform crustaceous; gonidia of Palmella, Trentepohlia, 

 or Phyllactidium algae. Apothecia forming irregular dots, lines, or 

 spots, simple or branched; single or forming a stroma, without proper 

 margin. But one genus occurs with us. 



