THE LICHEN FLORA OF THE SANTA CRUZ PENINSULA 249 



Thallus of medium size or large, rarely small with us, closely 

 appressed, with a radiately lobed circumference, the crenate lobules 

 long and distinct; remainder of plant thicker, crustaceous, fissured, 

 of variously shaped areoles, plane or convex, smooth, or roughened; 

 color greenish yellow or straw-color, the margin much lighter than 

 the inner portion, which is often dusky; lobes of circumference 

 black-margined, as are sometimes all the areoles; KOH faintly 

 darker yellowish; CaC^C^ . 



Apothecia small, innate, soon emergent and sessile, from plane, 

 becoming strongly convex; color of disk brown, brownish-black 

 and black; the entire thalline margin finally disappearing; paraphy- 

 ses agglutinate, their pale yellow tips enlarged; epithecium granular, 

 brownish; hypothecium clear; thecium blue with I; spores short, 



blunt empsoid,^ 9 ^^^. 



Found but once within our limits, lining a "pot-hole" on the top 

 of a huge sandstone crag, on the summit of the range near Devils 

 Canon, altitude about 2500 feet. Very abundant and finely devel- 

 oped in the Inner Coast Range, occurring at Alum Rock Park, as 

 low as 300 feet, covering large areas of igneous rock. 



Occasionally the marginal lobes are absent and the central portion 

 is degenerate. 



Widely distributed over the temperate zone. 



3. RINODINA BISCHOFFI IMMERSA Korber. 

 Rinodina bischqffii immersa Korber, Parerga Lich. 75. 1865. 

 Rinodina bischqffii immersa Jatta, Syll. Lich. Ital. 272. 1900. 

 Lecanora bischoffii immersa Leighton, Lich. Fl. Grt. Brit. ed. 3, 



221. 1879. 



Thallus endolithic, of minute granules visible only with a good 

 lens, imparting a gray or bluish cast to the stone, or else entirely 

 absent; KOH- ;CaCl 2 2 -. 



Apothecia minute, numerous, immersed in tiny pits in the rock, 

 black, usually plane and below the surface; a thin paler or concolor- 

 ous margin more or less evident; paraphyses simple, their tips coher- 

 ent, broadly capitate, sometimes forked, umber-colored; epithecium, 

 broad, blackish brown; hypothecium dark brown; spores blunt 



